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  • 1. Akinsinde, Lewis O.
    et al.
    Glier, Tomke E.
    Schwartzkopf, Matthias
    Betker, Marie
    Nissen, Matz
    Witte, Maximilian
    Scheitz, Sarah
    Nweze, Christian
    Grimm-Lebsanft, Benjamin
    Gensch, Marc
    Chumakov, Andrei
    Baev, Ivan
    Schurmann, Ulrich
    Dankwort, Torben
    Fischer, Frank
    Martins, Michael
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Kienle, Lorenz
    Ruebhausen, Michael
    Surface characterization and resistance changes of silver-nanowire networks upon atmospheric plasma treatment2021In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 550, article id 149362Article in journal (Refereed)
    Abstract [en]

    Highly conductive silver-nanowire (Ag-NW) networks are used in composite materials as conductive channels. Their resistance tuning can be accomplished by changing the Ag-NW concentration, and, therefore, changing the network structure. In this study, an alternative pathway to resistance engineering of conductive Ag-NW networks by local atmospheric plasma treatment is employed. The corresponding changes in nanowire network morphology and crystallinity as a function of plasma etching time are investigated by time-resolved grazingincidence X-ray scattering, field-effect scanning electron microscopy, and X-ray photoelectron spectroscopy. Three characteristic etching phases are identified. The first two phases enable the controlled engineering of the electrical properties with different rates of resistance change, which results from changes in nanowire shape, network morphology, and different oxidation rates. Phase III is characterized by pronounced fragmentation and destruction of the Ag-NW networks. These results show the feasibility of atmospheric plasma treatments to tune the local electrical properties of conductive Ag-NW networks. Furthermore, we present a physical Monte Carlo model explaining the electrical network properties as a function of plasma etching time based on the network connectivity and a constant plasma etching rate of 570 ng s-1 cm-2.

  • 2.
    Alexakis, Alexandros Efraim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Engström, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Stamm, Arne
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Riazanova, Anastasia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Wallenberg Wood Sci Ctr WWSC, Tekn Ringen 56-58, SE-10044 Stockholm, Sweden..
    Brett, Calvin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, Hamburg, 22603, Germany.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, Hamburg, 22603, Germany.
    Syrén, Per-Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Fogelström, Linda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Reid, Michael S.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Modification of cellulose through physisorption of cationic bio-based nanolatexes - comparing emulsion polymerization and RAFT-mediated polymerization-induced self-assembly2021In: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270, Vol. 23, no 5, p. 2113-2122Article in journal (Refereed)
    Abstract [en]

    The polymerization of a bio-based terpene-derived monomer, sobrerol methacrylate (SobMA), was evaluated in the design of polymeric nanoparticles (nanolatexes). Their synthesis was accomplished by using emulsion polymerization, either by free-radical polymerization in the presence of a cationic surfactant or a cationic macroRAFT agent by employing RAFT-mediated polymerization-induced self-assembly (PISA). By tuning the length of the hydrophobic polymer, it was possible to control the nanoparticle size between 70 and 110 nm. The average size of the latexes in both wet and dry state were investigated by microscopy imaging and dynamic light scattering (DLS). Additionally, SobMA was successfully copolymerized with butyl methacrylate (BMA) targeting soft-core nanolatexes. The comparison of the kinetic profile of the cationically stabilized nanolatexes highlighted the differences of both processes. The SobMA-based nanolatexes yielded high T-g similar to 120 degrees C, while the copolymer sample exhibited a lower T-g similar to 50 degrees C, as assessed by Differential Scanning Calorimetry (DSC). Thereafter, the nanolatexes were adsorbed onto cellulose (filter paper), where they were annealed at elevated temperatures to result in polymeric coatings. Their morphologies were analysed by Field Emission Scanning Electron Microscopy (FE-SEM) and compared to a commercial sulfate polystyrene latex (PS latex). By microscopic investigation the film formation mechanism could be unravelled. Water contact angle (CA) measurements verified the transition from a hydrophilic to a hydrophobic surface after film formation had occured. The obtained results are promising for the toolbox of bio-based building blocks, focused on sobrerol-based monomers, to be used in emulsion polymerizations either for tailored PISA-latexes or facile conventional latex formation, in order to replace methyl methacrylate or other high T-g-monomers.

  • 3.
    Bera, Anup Kumar
    et al.
    UGC DAE Consortium Sci Res, Khandwa Rd, Indore 452001, India..
    Dev, Arun Singh
    UGC DAE Consortium Sci Res, Khandwa Rd, Indore 452001, India..
    Kuila, Manik
    UGC DAE Consortium Sci Res, Khandwa Rd, Indore 452001, India..
    Ranjan, Mukesh
    Inst Plasma Res, FCIPT, Bhat 382428, Gandhinagar, India..
    Pandit, Pallavi
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Schwartzkopf, Matthias
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;KTH Royal Inst Technol, S-10044 Stockholm, Sweden..
    Reddy, Varimalla R.
    UGC DAE Consortium Sci Res, Khandwa Rd, Indore 452001, India..
    Kumar, Dileep
    UGC DAE Consortium Sci Res, Khandwa Rd, Indore 452001, India..
    Morphology induced large magnetic anisotropy in obliquely grown nanostructured thin film on nanopatterned substrate2022In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 581, article id 152377Article in journal (Refereed)
    Abstract [en]

    The artificial tailoring of magnetic anisotropy by manipulating surface and interface morphology is attracting widespread interest for its application in spintronic and magnetic memory devices. Here oblique angle deposition on a nanopatterned rippled substrate is presented as a novel route of inducing large in-plane uniaxial magnetic anisotropy (UMA) in magnetic thin films. For this purpose, Cobalt films and rippled SiO2 substrates have been taken as a model system for the present study. Here, nanopatterned substrates are prepared by low energy ion beam erosion (IBE), above which films are deposited obliquely along and normal to the ripple directions. A clear anisotropy in the growth behavior has been observed due to the inhomogeneous in-plane organization of adatoms in the form of columns. The increased shadowing effect in the films deposited obliquely normal to the direction of the ripple patterns causes preferential coalescence of the columns along the substrate ripples, resulting in stronger in-plane UMA in the film. This peculiarity in magnetic behavior is addressed by considering the morphological anisotropy governed by enhanced shadowing effect, the shape anisotropy and the dipolar interactions among the magnetostatically coupled ripple structure.

  • 4.
    Betker, Marie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Harder, Constantin
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85; Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1.
    Erbes, Elisabeth
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85; Institute for X-ray Physics, Goettingen University, Friedrich Hund Platz 1, 37077 Goettingen, Germany, Friedrich Hund Platz 1.
    Heger, Julian Eliah
    Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1.
    Alexakis, Alexandros Efraim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Sochor, Benedikt
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Chen, Qing
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Schwartzkopf, Matthias
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Körstgens, Volker
    Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1.
    Müller-Buschbaum, Peter
    Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1; Heinz Maier-Leibnitz Zentrum (MLZ), Technical University of Munich, Lichtenbergstr. 1, 85748 Garching, Germany, Lichtenbergstr. 1.
    Schneider, Konrad
    Abteilung Werkstofftechnik, Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany.
    Techert, Simone Agnes
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85; Institute for X-ray Physics, Goettingen University, Friedrich Hund Platz 1, 37077 Goettingen, Germany, Friedrich Hund Platz 1.
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Sprayed Hybrid Cellulose Nanofibril-Silver Nanowire Transparent Electrodes for Organic Electronic Applications2023In: ACS Applied Nano Materials, E-ISSN 2574-0970, Vol. 6, no 14, p. 13677-13688Article in journal (Refereed)
    Abstract [en]

    In times of climate change and resource scarcity, researchers are aiming to find sustainable alternatives to synthetic polymers for the fabrication of biodegradable, eco-friendly, and, at the same time, high-performance materials. Nanocomposites have the ability to combine several favorable properties of different materials in a single device. Here, we evaluate the suitability of two kinds of inks containing silver nanowires for the fast, facile, and industrial-relevant fabrication of two different types of cellulose-based silver nanowire electrodes via layer-by-layer spray deposition only. The Type I electrode has a layered structure, which is composed of a network of silver nanowires sprayed on top of a cellulose nanofibrils layer, while the Type II electrode consists of a homogeneous mixture of silver nanowires and cellulose nanofibrils. A correlation between the surface structure, conductivity, and transparency of both types of electrodes is established. We use the Haacke figure of merit for transparent electrode materials to demonstrate the favorable influence of cellulose nanofibrils in the spray ink by identifying Type II as the electrode with the lowest sheet resistance (minimum 5 ± 0.04 Ω/sq), while at the same time having a lower surface roughness and shorter fabrication time than Type I. Finally, we prove the mechanical stability of the Type II electrode by bending tests and its long-time stability under ambient conditions. The results demonstrate that the mixed spray ink of silver nanowires and cellulose nanofibrils is perfectly suitable for the fast fabrication of highly conductive organic nanoelectronics on an industrial scale.

  • 5.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Deutsches Elektronen Synchrotron, Notkestraße 85, Hamburg, Germany.
    Forslund, Ola Kenji
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Nocerino, Elisabetta
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Kreuzer, L.P
    TU München, Germany.
    Widmann, T.
    TU München, Germany.
    Porcar, L.
    Institut Laue-Langevin, 71 Avenue des Martyrs, Grenoble, France.
    Yamada, N. L.
    High Energy Accelerator Research Organization (KEK), 203-1 Shirakata, Tokai, Naka 319-1106, Japan.
    Matsubara, Nami
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Månsson, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Müller-Buschbaum, P.
    TU München, Germany.
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsches Elektronen Synchrotron, Notkestraße 85, Hamburg, Germany.
    Humidity-Induced Nanoscale Restructuring in PEDOT:PSS and Cellulose Nanofibrils Reinforced Biobased Organic Electronics2021In: Advanced Electronic Materials, E-ISSN 2199-160X, Vol. 7, no 6, p. 2100137-, article id 2100137Article in journal (Refereed)
    Abstract [en]

    In times where research focuses on the use of organic polymers as a base for complex organic electronic applications and improving device efficiencies, degradation is still less intensively addressed in fundamental studies. Hence, advanced neutron scattering methods are applied to investigate a model system for organic electronics composed of the widely used conductive polymer blend poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) together with nanocellulose as flexible reinforcing template material. In particular, the impact of relative humidity (RH) on the nanostructure evolution is studied in detail. The implications are discussed from a device performance point of view and the changing nanostructure is correlated with macroscale physical properties such as conductivity. The first humidification (95% RH) leads to an irreversible decrease of conductivity. After the first humidification cycle, however, the conductivity can be reversibly regained when returning to low humidity values (5% RH), which is important for device manufacturing. This finding can directly contribute to an improved usability of emerging organic electronics in daily live.

  • 6.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Forslund, Ola Kenji
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Nocerino, Elisabetta
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Kreuzer, Lucas
    Wiedmann, Tobias
    Porcar, Lionel
    Yamada, Norifumi
    Matsubara, Nami
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Månsson, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Müller-Buschbaum, Peter
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Humidity-induced Nanoscale Restructuring in PEDOT:PSS and Cellulose reinforced Bio-based Organic ElectronicsManuscript (preprint) (Other academic)
  • 7.
    Brett, Calvin J.
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Montani, Annaclaudia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering. Politecn Milan, Dept Chem Mat & Chem Engn Giulio Natta, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy..
    Schwartzkopf, M.
    DESY, Notkestr 85, D-22607 Hamburg, Germany..
    van Benthem, R. A. T. M.
    Eindhoven Univ Technol, Lab Phys Chem SPC, Groene Loper 5, NL-5600 MB Eindhoven, Netherlands.;DSM Mat Sci Ctr, Urmonderbaan 22, NL-6167 RD Geleen, Netherlands..
    Jansen, J. F. G. A.
    DSM Mat Sci Ctr, Urmonderbaan 22, NL-6167 RD Geleen, Netherlands..
    Griffini, G.
    Politecn Milan, Dept Chem Mat & Chem Engn Giulio Natta, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy..
    Roth, Stephan Volkher
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Johansson, Mats K.G.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Revealing structural evolution occurring from photo-initiated polymer network formation2020In: Communications Chemistry, E-ISSN 2399-3669, Vol. 3, no 1, article id 88Article in journal (Refereed)
    Abstract [en]

    Photopolymerization is a key enabling technology offering spatial and temporal control to allow for future functional materials to be made to meet societal needs. However, gaining access to robust experimental techniques to describe the evolution of nanoscale morphology in photo-initiated polymeric systems has proven so far to be a challenging task. Here, we show that these physical transformations can be monitored and quantified at the nanoscale in situ and in real-time. It is demonstrated that the initial structural features of the liquid precursors significantly affect the final morphology and the physical properties of the resulting solid via the occurrence of local heterogeneities in the molecular mobility during the curing transformation. We have made visible how local physical arrestings in the liquid, associated with both cross-linking and vitrification, determine the length scale of the local heterogeneities forming upon curing, found to be in the 10-200nm range. Acomplete account of the structural evolution occurring during photopolymerisation is lacking. Here the physical changes occurring on the nanometer scale during photopolymerisation of acrylates are followed over time by FTIR, X-ray reflectometry, AFM, and GISAXS, offering insight into the mechanism by which initial composition influences the final morphology.

  • 8.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Deutsches Elektronen-Synchrotron DESY, Hamburg 22607, Germany.
    Mittal, Nitesh
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Mechanics.
    Ohm, Wiebke
    Deutsches Elektronen-Synchrotron (DESY), Notkestr. 85, 22607, Hamburg, Germany.
    Gensch, Marc
    Deutsches Elektronen-Synchrotron (DESY), Notkestr. 85, 22607, Hamburg, Germany.
    Kreuzer, Lucas P.
    Deutsches Elektronen-Synchrotron (DESY), Notkestr. 85, 22607, Hamburg, Germany.
    Körstgens, Volker
    Lehrstuhl für Funktionelle Materialien, Physik-Department, and ¶ Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universitat ̈ München, Garching 85748, Germany.
    Månsson, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Frielinghaus, Henrich
    Jülich Centre for Neutron Science at MLZ.
    Söderberg, Daniel
    KTH, Superseded Departments (pre-2005), Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. Deutsches Elektronen-Synchrotron DESY, Hamburg 22607, Germany.
    Water-Induced Structural Rearrangements on the Nanoscale in Ultrathin Nanocellulose Films2019In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 52, no 12, p. 4721-4728Article in journal (Refereed)
    Abstract [en]

    Many nanoscale biopolymer building blocks with defect-free molecular structure and exceptional mechanical properties have the potential to surpass the performance of existing fossil-based materials with respect to barrier properties, load-bearing substrates for advanced functionalities, as well as light-weight construction. Comprehension and control of performance variations of macroscopic biopolymer materials caused by humidity-driven structural changes at the nanoscale are imperative and challenging. A long-lasting challenge is the interaction with water molecules causing reversible changes in the intrinsic molecular structures that adversely affects the macroscale performance. Using in situ advanced X-ray and neutron scattering techniques, we reveal the structural rearrangements at the nanoscale in ultrathin nanocellulose films with humidity variations. These reversible rearrangements are then correlated with wettability that can be tuned. The results and methodology have general implications not only on the performance of cellulose-based materials but also for hierarchical materials fabricated with other organic and inorganic moisture-sensitive building blocks.

  • 9.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.
    Mittal, Nitesh
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Ohm, Wiebke
    DESY, Hamburg, Germany..
    Söderberg, Daniel
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. DESY, Hamburg, Germany..
    GISAS study of spray deposited metal precursor ink on a cellulose template2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 10.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics. DESY, Photon Sci, Hamburg, Germany.
    Mittal, Nitesh
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Ohm, Wiebke
    DESY, Photon Sci, Hamburg, Germany..
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. DESY, Photon Sci, Hamburg, Germany..
    In situ self-assembly study in bio-based thin films2018In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal (Other academic)
  • 11.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.
    Ohm, Wiebke
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Fricke, Bjorn
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Alexakis, Alexandros Efraim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Laarmann, Tim
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Hamburg Ctr Ultrafast Imaging CUI, D-22761 Hamburg, Germany..
    Korstgens, Volker
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Materialien, D-85748 Garching, Germany..
    Muller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Materialien, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, D-85748 Garching, Germany..
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Roth, Stephan, V
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Dept Fibre & Polymer Technol, Div Coating Technol, S-10044 Stockholm, Sweden..
    Nanocellulose-Assisted Thermally Induced Growth of Silver Nanoparticles for Optical Applications2021In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 13, no 23, p. 27696-27704Article in journal (Refereed)
    Abstract [en]

    Optically responsive materials are present in everyday life, from screens to sensors. However, fabricating large-area, fossil-free materials for functional biocompatible applications is still a challenge today. Nanocelluloses from various sources, such as wood, can provide biocompatibility and are emerging candidates for templating organic optoelectronics. Silver (Ag) in its nanoscale form shows excellent optical properties. Herein, we combine both materials using thin-film large-area spray-coating to study the fabrication of optical response applications. We characterize the Ag nanoparticle formation by X-ray scattering and UV-vis spectroscopy in situ during growth on the nanocellulose template. The morphology and optical properties of the nanocellulose film are compared to the rigid reference surface SiO2. Our results clearly show the potential to tailor the energy band gap of the resulting hybrid material.

  • 12.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics.
    Ohm, Wiebke
    Fricke, Björn
    Laarmann, Tim
    Körstgens, Volker
    Müller-Buschbaum, Peter
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Nanocellulose-Assisted Thermally-Induced Growth of Silver Nanoparticles for Optical ApplicationsManuscript (preprint) (Other academic)
  • 13.
    Brunova, Alica
    et al.
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Vegso, Karol
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia.;Slovak Acad Sci, Ctr Adv Mat Applicat, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Nadazdy, Vojtech
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia.;Slovak Acad Sci, Ctr Adv Mat Applicat, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Nadazdy, Peter
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Subair, Riyas
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Jergel, Matej
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia.;Slovak Acad Sci, Ctr Adv Mat Applicat, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Majkova, Eva
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia.;Slovak Acad Sci, Ctr Adv Mat Applicat, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Pandit, Pallavi
    DESY, D-22607 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. DESY, D-22607 Hamburg, Germany..
    Krasnansky, Alexander
    Boston Univ, Dept Phys, 233 Bay State Rd, Boston, MA 02215 USA..
    Hinderhofer, Alexander
    Univ Tubingen, Inst Appl Phys, Morgenstelle 10, D-72076 Tubingen, Germany..
    Schreiber, Frank
    Univ Tubingen, Inst Appl Phys, Morgenstelle 10, D-72076 Tubingen, Germany..
    Tian, Jianjun
    Univ Sci & Technol Beijing, Inst Adv Mat & Technol, Beijing 100083, Peoples R China..
    Siffalovic, Peter
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia.;Slovak Acad Sci, Ctr Adv Mat Applicat, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Structural and Trap-State Density Enhancement in Flash Infrared Annealed Perovskite Layers2021In: Advanced Materials Interfaces, ISSN 2196-7350, Vol. 8, no 14, article id 2100355Article in journal (Refereed)
    Abstract [en]

    Perovskite solar cells are well-known for their high energy conversion efficiency, low-temperature processing, and cost-effective production. Flash infrared annealing (FIRA) of slot-die cast perovskite precursors offers an attractive manufacturing route using high-throughput roll-to-roll technology. Despite the recent progress in FIRA perovskite annealing, the optimal composition of the perovskite precursor is yet to be developed. Here, the effect of methylammonium chloride (MACI) on the perovskite structure and trap-state density as a function ofthe FIRA annealing time is investigated. In situ real-time grazingincidence wide-angle X-ray scattering (GIWAXS) is employed to monitor the perovskite layer formation during FIRA annealing with millisecond temporal resolution. In addition, the density of states in the bandgap is estimated using ex situ energy-resolved electrochemical impedance spectroscopy. Evidence is found that adding 10% MACI into the perovskite precursor solution significantly improves the crystallographic orientation of the perovskite layers while reducing the trap-state density by one order of magnitude. In addition, using time-resolved GIWAXS, the most favorable time window for the FIRA processing of perovskite films with the lowest mosaicity and trap-state density is identified. The results are of general importance for elucidating the appropriate temporal windows in complex and fast-evolving crystallization processes.

  • 14.
    Bulut, Yusuf
    et al.
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany..
    Sochor, Benedikt
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Harder, Constantin
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany..
    Reck, Kristian
    Christian Albrechts Univ Kiel, Dept Mat Sci, Chair Multicomponent Mat, Fac Engn, Kaiserstr 2, D-24143 Kiel, Germany..
    Drewes, Jonas
    Christian Albrechts Univ Kiel, Dept Mat Sci, Chair Multicomponent Mat, Fac Engn, Kaiserstr 2, D-24143 Kiel, Germany..
    Xu, Zhuijun
    Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany..
    Jiang, Xiongzhuo
    Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany..
    Meinhardt, Alexander
    Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Univ Hamburg, Dept Phys, Notkestr 9-11, D-22607 Hamburg, Germany..
    Jeromin, Arno
    Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Kohantorabi, Mona
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Noei, Heshmat
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Keller, Thomas F.
    Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Univ Hamburg, Dept Phys, Notkestr 9-11, D-22607 Hamburg, Germany..
    Strunskus, Thomas
    Christian Albrechts Univ Kiel, Dept Mat Sci, Chair Multicomponent Mat, Fac Engn, Kaiserstr 2, D-24143 Kiel, Germany..
    Faupel, Franz
    Christian Albrechts Univ Kiel, Dept Mat Sci, Chair Multicomponent Mat, Fac Engn, Kaiserstr 2, D-24143 Kiel, Germany..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, Lichtenbergerstr 1, D-85748 Garching, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Diblock copolymer pattern protection by silver cluster reinforcement2023In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 15, no 38, p. 15768-15774Article in journal (Refereed)
    Abstract [en]

    Pattern fabrication by self-assembly of diblock copolymers is of significant interest due to the simplicity in fabricating complex structures. In particular, polystyrene-block-poly-4-vinylpyridine (PS-b-P4VP) is a fascinating base material as it forms an ordered micellar structure on silicon surfaces. In this work, silver (Ag) is applied using direct current magnetron sputter deposition and high-power impulse magnetron sputter deposition on an ordered micellar PS-b-P4VP layer. The fabricated hybrid materials are structurally analyzed by field emission scanning electron microscopy, atomic force microscopy, and grazing incidence small angle X-ray scattering. When applying simple aqueous posttreatment, the pattern is stable and reinforced by Ag clusters, making micellar PS-b-P4VP ordered layers ideal candidates for lithography. The pristine micellar pattern of the diblock copolymer PS-b-P4VP degrades upon drying of a water droplet, which can be stabilized and inhibited upon deposition of silver clusters.

  • 15. Cao, W.
    et al.
    Yin, S.
    Bitsch, M.
    Liang, S.
    Plank, M.
    Opel, M.
    Scheel, M. A.
    Gallei, M.
    Janka, O.
    Schwartzkopf, M.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, Hamburg, 22607, Germany..
    Müller-Buschbaum, P.
    In Situ Study of FePt Nanoparticles-Induced Morphology Development during Printing of Magnetic Hybrid Diblock Copolymer Films2022In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 32, no 4, p. 2107667-, article id 2107667Article in journal (Refereed)
    Abstract [en]

    The development of magnetic hybrid films containing diblock copolymers (DBCs) and magnetic nanoparticles (NPs) by printing is a highly promising method for scalable and low-cost fabrication. During printing, the drying and arrangement kinetics of the DBC and magnetic NPs play an important role in the film formation concerning morphology and magnetic properties. In this study, the morphology evolution of ultrahigh molecular weight DBC polystyrene-block-poly(methyl methacrylate) and magnetic iron platinum (FePt) NPs is investigated with grazing-incidence small-angle X-ray scattering (GISAXS) in situ during printing. For comparison, a pure DBC film is printed without FePt NPs under the same conditions. The GISAXS data suggest that the addition of NPs accelerates the solvent evaporation, leading to a faster film formation of the hybrid film compared to the pure film. As the solvent is almost evaporated, a metastable state is observed in both films. Compared with the pure film, such a metastable state continues longer during the printing process of the hybrid film because of the presence of FePt NPs, which inhibits the reorganization of the DBC chains. Moreover, investigations of the field-dependent magnetization and temperature-dependent susceptibility indicate that the printed hybrid film is superparamagnetic, which makes this film class promising for magnetic sensors.

  • 16.
    Cao, Wei
    et al.
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Xia, Senlin
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Jiang, Xinyu
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Appold, Michael
    Tech Univ Darmstadt, Ernst Berl Inst Tech & Macromol Chem, D-64287 Darmstadt, Germany..
    Opel, Matthias
    Bayer Akad Wissensch, Walther Meissner Inst, D-85748 Garching, Germany..
    Plank, Martina
    Tech Univ Darmstadt, Ernst Berl Inst Tech & Macromol Chem, D-64287 Darmstadt, Germany..
    Schaffrinna, Roy
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Kreuzer, Lucas P.
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Yin, Shanshan
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Gallei, Markus
    Saarland Univ, Chair Polymer Chem, D-66123 Saarbrucken, Germany..
    Schwartzkopf, Matthias
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Mueller-Buschbaurn, Peter
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, D-85748 Garching, Germany..
    Self-Assembly of Large Magnetic Nanoparticles in Ultrahigh Molecular Weight Linear Diblock Copolymer Films2020In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 12, no 6, p. 7557-7564Article in journal (Refereed)
    Abstract [en]

    The development of diblock copolymer (DBC) nanocomposite films containing magnetic nanoparticles (NPs) with diameters (D) over 20 nm is a challenging task. To host large iron oxide NPs (Fe3O4, D = 27 +/- 0.6 nm), an ultrahigh molecular weight (UHMW) linear DBC polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) is used as a template in the present work. Due to hydrogen bonding between the carboxylic acid ligands of the NPs and the ester groups in PMMA, the NPs show an affinity to the PMMA block. The localization of the NPs inside the DBC is investigated as a function of the NP concentration. At low NP concentrations, NPs are located preferentially at the interface between PS and PMMA domains to minimize the interfacial tension caused by the strong segregation strength of the UHMW DBC. At high NP concentrations (>= 10 wt %), chain-like NP aggregates (a head-to-tail orientation) are observed in the PMMA domains, resulting in a change of the morphology from sphere to ellipsoid for part of the PMMA domains. Magnetic properties of the hybrid films are probed via superconducting quantum interference device magnetometry. All hybrid films show ferrimagnetism and are promising for potential applications in magnetic data storage.

  • 17. Cao, Wei
    et al.
    Yin, Shanshan
    Plank, Martina
    Chumakov, Andrei
    Opel, Matthias
    Chen, Wei
    Kreuzer, Lucas P.
    Heger, Julian E.
    Gallei, Markus
    Brett, Calvin J.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Schwartzkopf, Matthias
    Eliseev, Artem A.
    Anokhin, Evgeny O.
    Trusov, Lev A.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Mueller-Buschbaum, Peter
    Spray-Deposited Anisotropic Ferromagnetic Hybrid Polymer Films of PS-b-PMMA and Strontium Hexaferrite Magnetic Nanoplatelets2021In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 13, no 1, p. 1592-1602Article in journal (Refereed)
    Abstract [en]

    Spray deposition is a scalable and cost-effective technique for the fabrication of magnetic hybrid films containing diblock copolymers (DBCs) and magnetic nanoparticles. However, it is challenging to obtain spray-deposited anisotropic magnetic hybrid films without using external magnetic fields. In the present work, spray deposition is applied to prepare perpendicular anisotropic magnetic hybrid films by controlling the orientation of strontium hexaferrite nanoplatelets inside ultra-high-molecular-weight DBC polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) films. During spray deposition, the evolution of DBC morphology and the orientation of magnetic nanoplatelets are monitored with in situ grazing-incidence small-angle X-ray scattering (GISAXS). For reference, a pure DBC film without nanoplatelets is deposited with the same conditions. Solvent-controlled magnetic properties of the hybrid film are proven with solvent vapor annealing (SVA) applied to the final deposited magnetic films. Obvious changes in the DBC morphology and nanoplatelet localization are observed during SVA. The superconducting quantum interference device data show that ferromagnetic hybrid polymer films with high coercivity can be achieved via spray deposition. The hybrid films show a perpendicular magnetic anisotropy before SVA, which is strongly weakened after SVA. The spray-deposited hybrid films appear highly promising for potential applications in magnetic data storage and sensors.

  • 18. Chang, B.
    et al.
    Schneider, K.
    Patil, N.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. DESY, Hamburg, Germany.
    Heinrich, G.
    Microstructure characterization in a single isotactic polypropylene spherulite by synchrotron microfocus wide angle X-ray scattering2018In: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 142, p. 387-393Article in journal (Refereed)
    Abstract [en]

    Position-resolved microstructure in a single spherulite of iPP is quantitatively studied by synchrotron microfocus wide angle X-ray scattering. The results show that the normal of mother lamellae in a spherulite is aligned mainly perpendicular to the radius, and the subsidiary daughter lamellae are inclined 80.75° with respect to that of the dominant mother lamellae. The crystallinity in the spherulite is in the range of 46%–56%, which is rarely influenced by the crystallization temperature. The ratio between the daughter lamellae and the mother lamellae is 0.18 when iPP crystallizes at 138 °C and it decreases to 0.11 as the crystallization temperature is decreased to 130 °C. The b-axis and c-axis in the mother lamellae tend to orient perpendicular to the radius direction, and the a-axis prefers to align in the radius direction.

  • 19. Chen, Q.
    et al.
    Betker, Marie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, Hamburg, 22607, Germany.
    Harder, C.
    Brett, Calvin J.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, Hamburg, 22607, Germany.
    Schwartzkopf, M.
    Ulrich, N. M.
    Toimil-Molares, M. E.
    Trautmann, C.
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Weindl, C. L.
    Körstgens, V.
    Müller-Buschbaum, P.
    Ma, M.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, Hamburg, 22607, Germany.
    Biopolymer-Templated Deposition of Ordered and Polymorph Titanium Dioxide Thin Films for Improved Surface-Enhanced Raman Scattering Sensitivity2022In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 32, no 6, article id 2108556Article in journal (Refereed)
    Abstract [en]

    Titanium dioxide (TiO2) is an excellent candidate material for semiconductor metal oxide-based substrates for surface-enhanced Raman scattering (SERS). Biotemplated fabrication of TiO2 thin films with a 3D network is a promising route for effectively transferring the morphology and ordering of the template into the TiO2 layer. The control over the crystallinity of TiO2 remains a challenge due to the low thermal stability of biopolymers. Here is reported a novel strategy of the cellulose nanofibril (CNF)-directed assembly of TiO2/CNF thin films with tailored morphology and crystallinity as SERS substrates. Polymorphous TiO2/CNF thin films with well-defined morphology are obtained by combining atomic layer deposition and thermal annealing. A high enhancement factor of 1.79 × 106 in terms of semiconductor metal oxide nanomaterial (SMON)-based SERS substrates is obtained from the annealed TiO2/CNF thin films with a TiO2 layer thickness of 10 nm fabricated on indium tin oxide (ITO), when probed by 4-mercaptobenzoic acid molecules. Common SERS probes down to 10 nm can be detected on these TiO2/CNF substrates, indicating superior sensitivity of TiO2/CNF thin films among SMON SERS substrates. This improvement in SERS sensitivity is realized through a cooperative modulation of the template morphology of the CNF network and the crystalline state of TiO2.

  • 20. Chen, Q.
    et al.
    Sochor, B.
    Chumakov, A.
    Betker, Marie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Ulrich, N. M.
    Toimil-Molares, M. E.
    Gordeyeva, Korneliya
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Cellulose-Reinforced Programmable and Stretch-Healable Actuators for Smart Packaging2022In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 32, no 49, p. 2208074-, article id 2208074Article in journal (Refereed)
    Abstract [en]

    Biomimetic actuators are promising candidates for smart soft robotics. The applications of state-of-the-art actuators require the combination of programmable stimuli-responsiveness, excellent robustness, and efficient self-healing ability in a wide-range of working conditions. However, these properties may be mutually exclusive. Inspired by biological tissues, two kinds of polyelectrolytes including polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS) are exploited as the fillers of cellulose nanofibrils (CNFs) for the fabrication of the CNF/PVA/PSS (CAS) film via the assembly of the physically-crosslinked network through multiple H-bonding and electrostatic interactions. Achieved by a casting-evaporation strategy, internal stress is stored within the polymer matrix and transforms into reversible anisotropic bending deformations in response to a humidity gradient. The speed, direction, and pitch of the bending can be programmed by tailoring the internal stresses and geometry of the samples. Moreover, the H-bonded network also contributes to the effective energy dissipation toward high toughness during tensile stretching, as well as self-healing ability during moisture saturation of the CAS films. This enables the fabrication of a humidity-sensitive flower-shaped actuator and self-healable packaging paper. This study presents a biomimetic strategy for the fabrication of multi-functional soft robotics, which holds great promise for applications in the fields of biosensors and smart packaging. 

  • 21.
    Chen, Qing
    et al.
    DESY, D-22607 Hamburg, Germany.;Univ Sci & Technol China, Sch Chem & Mat Sci, Hefei 230026, Peoples R China..
    Brett, Calvin
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. DESY, D-22607 Hamburg, Germany..
    Chumakov, Andrei
    DESY, D-22607 Hamburg, Germany..
    Gensch, Marc
    DESY, D-22607 Hamburg, Germany.;Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany..
    Schwartzkopf, Matthias
    DESY, D-22607 Hamburg, Germany..
    Koerstgens, Volker
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany..
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Plech, Anton
    Karlsruhe Inst Technol KIT, Inst Photon Sci & Synchrotron Radiat, D-76021 Karlsruhe, Germany..
    Zhang, Peng
    Sun Yat Sen Univ, Sch Mat Sci & Engn, PCFM Lab, Guangzhou 510275, Peoples R China..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibniz Zentrum MLZ, D-85748 Garching, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. DESY, D-22607 Hamburg, Germany..
    Layer-by-Layer Spray-Coating of Cellulose Nanofibrils and Silver Nanoparticles for Hydrophilic Interfaces2021In: ACS Applied Nano Materials, E-ISSN 2574-0970, Vol. 4, no 1, p. 503-513Article in journal (Refereed)
    Abstract [en]

    Silver nanoparticles (AgNPs) and AgNP-based composite materials have attracted growing interest due to their structure-dependent optical, electrical, catalytic, and stimuli-responsive properties. For practical applications, polymeric materials are often combined with AgNPs to provide flexibility and offer a scaffold for homogenous distribution of the AgNPs. However, the control over the assembly process of AgNPs on polymeric substrates remains a big challenge. Herein, we report the fabrication of AgNP/cellulose nanofibril (CNF) thin films via layer-by-layer (LBL) spray-coating. The morphology and self-assembly of AgNPs with increasing number of spray cycles are characterized by atomic force microscopy (AFM), grazing-incidence small-angle X-ray scattering (GISAXS), and grazing-incidence wide-angle X-ray scattering (GIWAXS). We deduce that an individual AgNP (radius = 15 +/- 3 nm) is composed of multiple nanocrystallites (diameter = 2.4 +/- 0.9 nm). Our results suggest that AgNPs are assembled into large agglomerates on SiO2 substrates during spray-coating, which is disadvantageous for AgNP functionalization. However, the incorporation of CNF substrates contributes to a more uniform distribution of AgNP agglomerates and individual AgNPs by its network structure and by absorbing the partially dissolved AgNP agglomerates. Furthermore, we demonstrate that the spray-coating of the AgNP/CNF mixture results in similar topography and agglomeration patterns of AgNPs compared to depositing AgNPs onto a precoated CNF thin film. Contact-angle measurements and UV/vis spectroscopy suggest that the deposition of AgNPs onto or within CNFs could increase the hydrophilicity of AgNP-containing surfaces and the localized surface plasmon resonance (LSPR) intensity of AgNP compared to AgNPs sprayed on SiO(2 )substrates, suggesting their potential applications in antifouling coatings or label-free biosensors. Thereby, our approach provides a platform for a facile and scalable production of AgNP/CNF films with a low agglomeration rate by two different methods as follows: (1) multistep layer-by-layer (LBL) spray-coating and (2) direct spray-coating of the AgNP/CNF mixture. We also demonstrate the ability of CNFs as a flexible framework for directing the uniform assembly of AgNPs with tailorable wettability and plasmonic properties.

  • 22. Chen, W.
    et al.
    Guo, R.
    Tang, H.
    Wienhold, K. S.
    Li, N.
    Jiang, Z.
    Tang, J.
    Jiang, X.
    Kreuzer, L. P.
    Liu, H.
    Schwartzkopf, M.
    Sun, X. W.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany.
    Wang, K.
    Xu, B.
    Müller-Buschbaum, P.
    Operando structure degradation study of PbS quantum dot solar cells2021In: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 14, no 6, p. 3420-3429Article in journal (Refereed)
    Abstract [en]

    PbS quantum dot (QD) solar cells demonstrate great potential in solar energy conversion with a broad and flexible spectral response. Even though long-term storage stabilities of QD solar cells were reported in literature, the operation stability from a more practical aspect, to date, has been not yet investigated. Herein, we observe the structure degradation process of a PbS QD-ink based solar cell during the device operation. Simultaneously to probing the solar cell parameters, the overall structure evolutions of the QDs in both, active layer and hole transport layer of the solar cell are studied with grazing-incidence small- and wide-angle X-ray scattering (GISAXS/GIWAXS). We find a spontaneous decrease of the QD inter-dot distance with an increase in the spatial disorder in the active layer (PbX2-PbS QDs, X = I, and Br) during the operation induced degradation. Consequently, the structure disorder-induced broadening of the energy state distribution is responsible for the decrease in open-circuit voltageVocleading to the device degradation. These findings elucidate the origin of light-soaking as well as the structure degradation of QD ink-based solar cells and indicate that the stability of the device can be realized by the positional stabilization of the QDs in the QD solid.

  • 23.
    Chen, Wei
    et al.
    Physik Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany.
    Liang, Suzhe
    Physik Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany.
    Löhrer, Franziska C.
    Physik Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany.
    Schaper, Simon J.
    Physik Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany.
    Li, Nian
    Physik Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany.
    Cao, Wei
    Physik Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany.
    Kreuzer, Lucas P.
    Physik Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany.
    Liu, Haochen
    Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Xueyuan Blvd. 1088, 518055 Shenzhen, China.
    Tang, Haodong
    Körstgens, Völker
    Physik Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany.
    Schwartzkopf, Matthias
    Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany.
    Wang, Kai
    Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Xueyuan Blvd. 1088, 518055 Shenzhen, China.
    Sun, X. W.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Müller-Buschbaum, P.
    In situ Grazing-Incidence Small-Angle X-ray Scattering Observation of Gold Sputter Deposition on a PbS Quantum Dot Solid2020In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 12, no 41, p. 46942-46952Article in journal (Refereed)
    Abstract [en]

    For PbS quantum dot (QD)-based optoelectronic devices, gold is the most frequently used electrode material. In most device architectures, gold is in direct contact with the QD solid. To better understand the formation of the interface between gold and a close-packed QD layer at an early stage, in situ grazing-incidence small-angle X-ray scattering is used to observe the gold sputter deposition on a 1,2-ethanedithiol (EDT)-treated PbS QD solid. In the kinetics of gold layer growth, the forming and merging of small gold clusters (radius less than 1.6 nm) are observed at the early stages. The thereby formed medium gold clusters (radius between 1.9-2.4 nm) are influenced by the QDs' templating effect. Furthermore, simulations suggest that the medium gold clusters grow preferably along the QDs' boundaries rather than as a top coating of the QDs. When the thickness of the sputtered gold layer reaches 6.25 nm, larger gold clusters with a radius of 5.3 nm form. Simultaneously, a percolation layer with a thickness of 2.5 nm is established underneath the gold clusters. This fundamental understanding of the QD-gold interface formation will help to control the implementation of sputtered gold electrodes on close-packed QD solids in device manufacturing processes.

  • 24.
    Chen, Wei
    et al.
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Tang, Haodong
    Southern Univ Sci & Technol SUSTech, Dept Elect & Elect Engn, Xueyuan Blvd 1088, Shenzhen 518055, Peoples R China..
    Li, Nian
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Scheel, Manuel A.
    Southern Univ Sci & Technol SUSTech, Dept Elect & Elect Engn, Xueyuan Blvd 1088, Shenzhen 518055, Peoples R China..
    Xie, Yue
    Southern Univ Sci & Technol SUSTech, Dept Elect & Elect Engn, Xueyuan Blvd 1088, Shenzhen 518055, Peoples R China..
    Li, Depeng
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Koerstgens, Volker
    DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Schwartzkopf, Matthias
    Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, 22607 Hamburg, Germany.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, 22607 Hamburg, Germany.
    Wang, Kai
    Southern Univ Sci & Technol SUSTech, Dept Elect & Elect Engn, Xueyuan Blvd 1088, Shenzhen 518055, Peoples R China..
    Sun, Xiao Wei
    Southern Univ Sci & Technol SUSTech, Dept Elect & Elect Engn, Xueyuan Blvd 1088, Shenzhen 518055, Peoples R China..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, Lichtenbergstr 1, D-85748 Garching, Germany..
    Colloidal PbS quantum dot stacking kinetics during deposition via printing2020In: Nanoscale Horizons, ISSN 2055-6764, E-ISSN 2055-6756, Vol. 5, no 5, p. 880-885Article in journal (Refereed)
    Abstract [en]

    Colloidal PbS quantum dots (QDs) are attractive for solution-processed thin-film optoelectronic applications. In particular, directly achieving QD thin-films by printing is a very promising method for low-cost and large-scale fabrication. The kinetics of QD particles during the deposition process play an important role in the QD film quality and their respective optoelectronic performance. In this work, the particle self-organization behavior of small-sized QDs with an average diameter of 2.88 +/- 0.36 nm is investigated for the first time in situ during printing by grazing-incidence small-angle X-ray scattering (GISAXS). The time-dependent changes in peak intensities suggest that the structure formation and phase transition of QD films happen within 30 seconds. The stacking of QDs is initialized by a templating effect, and a face-centered cubic (FCC) film forms in which a superlattice distortion is also found. A body-centered cubic nested FCC stacking is the final QD assembly layout. The small size of the inorganic QDs and the ligand collapse during the solvent evaporation can well explain this stacking behavior. These results provide important fundamental understanding of structure formation of small-sized QD based films prepared via large-scale deposition with printing with a slot die coater.

  • 25.
    Chernova, E. A.
    et al.
    Lomonosov Moscow State Univ, Dept Mat Sci, 1-73 Leninskiye Gory, Moscow 119991, Russia..
    Petukhov, D. I.
    Lomonosov Moscow State Univ, Dept Mat Sci, 1-73 Leninskiye Gory, Moscow 119991, Russia.;Lomonosov Moscow State Univ, Dept Chem, 1-3 Leninskiye Gory, Moscow 119991, Russia..
    Chumakov, A. P.
    DESY Deutsch Elekt Synchrotron, Notkestr 85, D-22607 Hamburg, Germany..
    Kirianova, A. V.
    Lomonosov Moscow State Univ, Dept Mat Sci, 1-73 Leninskiye Gory, Moscow 119991, Russia..
    Sadilov, I. S.
    Lomonosov Moscow State Univ, Dept Mat Sci, 1-73 Leninskiye Gory, Moscow 119991, Russia..
    Kapitanova, O. O.
    Lomonosov Moscow State Univ, Dept Chem, 1-3 Leninskiye Gory, Moscow 119991, Russia..
    Boytsova, O. V.
    Lomonosov Moscow State Univ, Dept Mat Sci, 1-73 Leninskiye Gory, Moscow 119991, Russia.;RAS, Kurnakov Inst Gen & Inorgan Chem, Leninsky Ave 31, Moscow 119991, Russia..
    Valeev, R. G.
    Russian Acad Sci UdmFRC UB RAS, Udmurt Fed Res Ctr, Ural Brunch, St Them Tatiana Baramzina 34, Izhevsk 426067, Russia..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. DESY Deutsch Elekt Synchrotron, Notkestr 85, D-22607 Hamburg, Germany..
    Eliseev, Ar A.
    Lomonosov Moscow State Univ, Dept Chem, 1-3 Leninskiye Gory, Moscow 119991, Russia..
    Eliseev, An A.
    Lomonosov Moscow State Univ, Dept Mat Sci, 1-73 Leninskiye Gory, Moscow 119991, Russia..
    The role of oxidation level in mass-transport properties and dehumidification performance of graphene oxide membranes2021In: Carbon, ISSN 0008-6223, E-ISSN 1873-3891, Vol. 183, p. 404-414Article in journal (Refereed)
    Abstract [en]

    Here we report on gas and vapor transport properties of ultra-thin graphene oxide (GO) membranes, with various C:O ratios. Graphene oxide nanosheets with an average lateral size of 800 nm and C:O ratio ranging from 2.11 to 1.81 have been obtained using improved Hummers' method by variation of graphite:KMnO4 ratio. Thin-film selective layers based on the obtained graphene oxide have been spin-coated onto porous substrates. To extend the C:O range to 2.60, thermal reduction of GO membranes was applied. A decrease in C:O ratio leads to significant water vapor permeance growth to over 60 m(3)(STP).m(-2).bar(-1).h(-1) while the permeance towards permanent gases reduces slightly. According to the permeation and sorption measurements, a decisive role of H2O diffusivity has been established, while the water sorption capacity of the graphene oxide stays nearly independent of C:O ratio in GO. The result is supported by semi-empirical modeling which reveals diminution of H2O jump activation barriers with both increasing GO interlayer spacing and its oxidation degree. The height of the activation barriers was found to vary up to an order of magnitude within the entire range of relative humidity (0-100% RH), lowering significantly for strongly oxidized GO. Our results evidence the necessity of attaining maximum GO oxidation degree for improving water transport in GO, especially at low partial pressures.

  • 26.
    Chumakova, Aleksandra
    et al.
    Outstation at Heinz Maier-Leibnitz Zentrum (MLZ), Institute of Crystallography (IfK), RWTH Aachen University, Lichtenbergstrasse 1, Garching, 85747, Germany; European Synchrotron Radiation Facility, 71 Avenue des Martyrs, Grenoble, 38000, France.
    Kirner, Felizitas
    Department of Earth and Environmental Sciences, Section of Crystallography, Ludwig-Maximilians-Universität München (LMU), Theresienstr. 41C, Munich, 80333, Germany.
    Chumakov, Andrei
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, Hamburg, 22607, Germany.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, Hamburg, 22607, Germany.
    Bosak, Alexeï
    European Synchrotron Radiation Facility, 71 Avenue des Martyrs, Grenoble, 38000, France.
    Sturm, Elena V.
    Department of Earth and Environmental Sciences, Section of Crystallography, Ludwig-Maximilians-Universität München (LMU), Theresienstr. 41C, Munich, 80333, Germany.
    Exploring the Crystalline Structure of Gold Mesocrystals Using X-ray Diffraction2023In: Crystals, ISSN 2073-4352, Vol. 13, no 8, article id 1204Article in journal (Refereed)
    Abstract [en]

    Mesocrystals are a class of nanostructured material where individual nanocrystals are arranged in a distinct crystallographic orientation. The multiple-length-scale order in such materials plays an essential role in the emergent physical and chemical phenomena. Our work studies the structure of a faceted mesocrystal composed of polystyrene-functionalized single crystalline gold nanoparticles using complementary ultrasmall- and wide-angle X-ray scattering (USAXS and WAXS) with electron microscopy. The results of the data analysis shed some light on the details of the microscopic structure of mesocrystals and their structuration principle.

  • 27.
    Coupette, Fabian
    et al.
    Univ Freiburg, Inst Phys, Hermann Herder Str 3, D-79104 Freiburg, Germany..
    Zhang, Long
    INM Leibniz Inst New Mat, Campus D2 2, D-66123 Saarbrucken, Germany..
    Kuttich, Bjoern
    INM Leibniz Inst New Mat, Campus D2 2, D-66123 Saarbrucken, Germany..
    Chumakov, Andrei
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;.
    Gonzalez-Garcia, Lola
    INM Leibniz Inst New Mat, Campus D2 2, D-66123 Saarbrucken, Germany..
    Kraus, Tobias
    INM Leibniz Inst New Mat, Campus D2 2, D-66123 Saarbrucken, Germany.;Saarland Univ, Colloid & Interface Chem, Campus D2 2, D-66123 Saarbrucken, Germany..
    Schilling, Tanja
    Univ Freiburg, Inst Phys, Hermann Herder Str 3, D-79104 Freiburg, Germany..
    Percolation of rigid fractal carbon black aggregates2021In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 155, no 12, article id 124902Article in journal (Refereed)
    Abstract [en]

    We examine network formation and percolation of carbon black by means of Monte Carlo simulations and experiments. In the simulation, we model carbon black by rigid aggregates of impenetrable spheres, which we obtain by diffusion-limited aggregation. To determine the input parameters for the simulation, we experimentally characterize the micro-structure and size distribution of carbon black aggregates. We then simulate suspensions of aggregates and determine the percolation threshold as a function of the aggregate size distribution. We observe a quasi-universal relation between the percolation threshold and a weighted average radius of gyration of the aggregate ensemble. Higher order moments of the size distribution do not have an effect on the percolation threshold. We conclude further that the concentration of large carbon black aggregates has a stronger influence on the percolation threshold than the concentration of small aggregates. In the experiment, we disperse the carbon black in a polymer matrix and measure the conductivity of the composite. We successfully test the hypotheses drawn from simulation by comparing composites prepared with the same type of carbon black before and after ball milling, i.e., on changing only the distribution of aggregate sizes in the composites.& nbsp;

  • 28. Dev, A. S.
    et al.
    Kumar, D.
    Potdar, S.
    Pandit, P.
    Roth, Stephan Volkher
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Photon Science, DESY, Notkestrasse 85, Hamburg, Germany.
    Gupta, A.
    Portable mini-chamber for temperature dependent studies using small angle and wide angle x-ray scattering2018In: DAE Solid State Physics Symposium 2017, American Institute of Physics (AIP), 2018, Vol. 1942, article id 080057Conference paper (Refereed)
    Abstract [en]

    The present work describes the design and performance of a vacuum compatible portable mini chamber for temperature dependent GISAXS and GIWAXS studies of thin films and multilayer structures. The water cooled body of the chamber allows sample annealing up to 900 K using ultra high vacuum compatible (UHV) pyrolytic boron nitride heater, thus making it possible to study the temperature dependent evolution of structure and morphology of two-dimensional nanostructured materials. Due to its light weight and small size, the chamber is portable and can be accommodated at synchrotron facilities worldwide. A systematic illustration of the versatility of the chamber has been demonstrated at beamline P03, PETRA-III, DESY, Hamburg, Germany. Temperature dependent grazing incidence small angle x-ray scattering (GISAXS) and grazing incidence wide angle x-ray scattering (GIWAXS) measurements were performed on oblique angle deposited Co/Ag multilayer structure, which jointly revealed that the surface diffusion in Co columns in Co/Ag multilayer enhances by increasing temperature from RT to ∼573 K. This results in a morphology change from columnar tilted structure to densely packed morphological isotropic multilayer

  • 29.
    Engström, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Brett, Calvin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Mechanics.
    Körstgens, V.
    Müller-Buschbaum, P.
    Ohm, W.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Core–Shell Nanoparticle Interface and Wetting Properties2020In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 30, no 15, article id 1907720Article in journal (Refereed)
    Abstract [en]

    Latex colloids are among the most promising materials for broad thin film applications due to their facile surface functionalization. Yet, the effect of these colloids on chemical film and wetting properties cannot be easily evaluated. At the nanoscale, core–shell particles can deform and coalesce during thermal annealing, yielding fine-tuned physical properties. Two different core–shell systems (soft and rigid) with identical shells but with chemically different core polymers and core sizes are investigated. The core–shell nanoparticles (NPs) are probed during thermal annealing in order to investigate their behavior as a function of nanostructure size and rigidity. X-ray scattering allows to follow the re-arrangement of the NPs and the structural evolution in situ during annealing. Evaluation by real-space imaging techniques reveals a disappearance of the structural integrity and a loss of NP boundaries. The possibility to fine-tune the wettability by tuning the core–shell NPs morphology in thin films provides a facile template methodology for repellent surfaces.

  • 30.
    Engström, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Brett, Calvin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Film formation of soft and rigid PISA‐latexes –analysis of thin films using GISAXSManuscript (preprint) (Other academic)
  • 31.
    Euchler, E.
    et al.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Sambale, A. K.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Schneider, K.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Uhlig, K.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Boldt, R.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Stommel, M.
    Leibniz-Institut für Polymerforschung, Dresden, Germany; Technische Universität Dresden, Germany.
    Stribeck, A.
    Universität Hamburg, Germany.
    Schwartzkopf, M.
    Deutsches Elektronen-Synchrotron, Hamburg, Germany.
    Rothkirch, A.
    Deutsches Elektronen-Synchrotron, Hamburg, Germany.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Deutsches Elektronen-Synchrotron, Hamburg, Germany.
    Beamline-implemented stretching devices for in situ X-ray scattering experiments2022Conference paper (Refereed)
    Abstract [en]

    Two recently developed experimental devices for investigating soft matter deformation are presented. Both devices exploit the capabilities of a modern synchrotron beamline to enable advanced and highly precise materials-science experiments in which X-ray scattering is registered. The devices can be operated both in monotonic as well as cyclic mode and are implemented into a beamline at DESY, Hamburg (Germany). Hence, relevant experimental parameters, such as displacement, force and temperature, are recorded synchronously with the individual X-ray scattering patterns. In addition, spatial variation of materials deformation can be monitored and recorded with optical microscopy. This unique sample environment enables in situ X-ray experiments in transmission, i.e. small- or wide-angle X-ray scattering (SAXS or WAXS), and in grazing-incidence geometry, i.e. grazing-incidence (GI-) SAXS or WAXS. One device with stepper motors is designed for studies of slow, (quasi-) static deformation and the other one with pneumatic actuators can be used for fast, impact deformation. Both devices are available to external beamline users, too.

  • 32.
    Gensch, Marc
    et al.
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany..
    Schwartzkopf, Matthias
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Brett, Calvin
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.
    Schaper, Simon J.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany..
    Kreuzer, Lucas P.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany..
    Li, Nian
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany..
    Chen, Wei
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany..
    Liang, Suzhe
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany..
    Drewes, Jonas
    Christian Albrechts Univ Kiel, Inst Mat Wissensch, Lehrstuhl Mat Verbunde, D-24143 Kiel, Germany..
    Polonskyi, Oleksandr
    Christian Albrechts Univ Kiel, Inst Mat Wissensch, Lehrstuhl Mat Verbunde, D-24143 Kiel, Germany..
    Strunskus, Thomas
    Christian Albrechts Univ Kiel, Inst Mat Wissensch, Lehrstuhl Mat Verbunde, D-24143 Kiel, Germany..
    Faupel, Franz
    Christian Albrechts Univ Kiel, Inst Mat Wissensch, Lehrstuhl Mat Verbunde, D-24143 Kiel, Germany..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibniz Zentrum MLZ, D-85748 Garching, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;KTH Royal Inst Technol, Dept Fiber & Polymer Technol, SE-10044 Stockholm, Sweden..
    Selective Silver Nanocluster Metallization on Conjugated Diblock Copolymer Templates for Sensing and Photovoltaic Applications2021In: ACS Applied Nano Materials, E-ISSN 2574-0970, Vol. 4, no 4, p. 4245-4255Article in journal (Refereed)
    Abstract [en]

    Polymer-metal composite films with nanostructured metal and/or polymer interfaces show a significant perspective for optoelectronic applications, for example, as sensors or in organic photovoltaics (OPVs). The polymer components used in these devices are mostly nanostructured conductive polymers with conjugated pi-electron systems. Enhanced OPV's power conversion efficiencies or sensor sensitivity can be achieved by selective metal deposition on or into polymer templates. In this study, we exploit time-resolved grazing-incidence X-ray scattering to observe the metal-polymer interface formation and the cluster crystallite size in situ during silver (Ag) sputter deposition on a poly(3-hexylthiophene-2,5-diyl)-b-poly(methyl methacrylate) (PMMA-b-P3HT) template. We compare the arising nanoscale morphologies with electronic properties, determine Ag growth regimes, and quantify the selective Ag growth for the diblock copolymer (DBC) template using the corresponding homopolymer thin films (P3HT and PMMA) as a reference. Hence, we are able to describe the influence of the respective polymer blocks and substrate effects on the Ag cluster percolation: the percolation threshold is correlated with the insulator-to-metal transition measured in situ with resistance measurements during the sputter deposition. The Ag cluster percolation on PMMA-b-P3HT starts already on the network of the hexagonal P3HT domain before a complete metal film covers the polymer surface, which is complemented by microscopic measurements. In general, this study demonstrates a possible method for the selective Ag growth as a scaffold for electrode preparation in nanoelectronics and for energy harvesting applications.

  • 33.
    Gensch, Marc
    et al.
    DESY, D-22607 Hamburg, Germany.;Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Schwartzkopf, Matthias
    DESY, D-22607 Hamburg, Germany..
    Brett, Calvin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics. DESY, D-22607 Hamburg, Germany.;.
    Schaper, Simon J.
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Li, Nian
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Chen, Wei
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Liang, Suzhe
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany..
    Drewes, Jonas
    Christian Albrechts Univ Kiel, Lehrstuhl Mat Verbunde, Inst Mat Wissensch, D-24143 Kiel, Germany..
    Polonskyi, Oleksandr
    Univ Calif Santa Barbara, Gordon Lab, Santa Barbara, CA 93106 USA..
    Strunskus, Thomas
    Christian Albrechts Univ Kiel, Lehrstuhl Mat Verbunde, Inst Mat Wissensch, D-24143 Kiel, Germany..
    Faupel, Franz
    Christian Albrechts Univ Kiel, Lehrstuhl Mat Verbunde, Inst Mat Wissensch, D-24143 Kiel, Germany..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibniz Zentrum MLZ, D-85748 Garching, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. DESY, D-22607 Hamburg, Germany..
    Correlating Optical Reflectance with the Topology of Aluminum Nanocluster Layers Growing on Partially Conjugated Diblock Copolymer Templates2021In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 13, no 47, p. 56663-56673Article in journal (Refereed)
    Abstract [en]

    Large-scale fabrication of metal cluster layers for usage in sensor applications and photovoltaics is a huge challenge. Physical vapor deposition offers large-scale fabrication of metal cluster layers on templates and polymer surfaces. In the case of aluminum (Al), only little is known about the formation and interaction of Al clusters during sputter deposition. Complex polymer surface morphologies can tailor the deposited Al cluster layer. Here, a poly(methyl methacrylate)-block-poly(3-hexylthiophen-2,5-diyl) (PMMA-b-P3HT) diblock copolymer template is used to investigate the nanostructure formation of Al cluster layers on the different polymer domains and to compare it with the respective homopolymers PMMA and P3HT. The optical properties relevant for sensor applications are monitored with ultraviolet-visible (UV-vis) measurements during the sputter deposition. The formation of Al clusters is followed in situ with grazing-incidence small-angle X-ray scattering (GISAXS), and the chemical interaction is revealed by X-ray photoelectron spectroscopy (XPS). Furthermore, atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM) yield topographical information about selective wetting of Al on the P3HT domains and embedding in the PMMA domains in the early stages, followed by four distinct growth stages describing the Al nanostructure formation.

  • 34.
    Gensch, Marc
    et al.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Schwartzkopf, Matthias
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Ohm, Wiebke
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Brett, Calvin
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics. Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Pandit, Pallavi
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Varalil, Sarathlal Koyiloth
    Indian Inst Sci, Dept Phys, Bangalore 560012, Karnataka, India..
    Biessmann, Lorenz
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Kreuzer, Lucas P.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Drewes, Jonas
    Christian Albrechts Univ Kiel, Inst Mat Wissensch, Lehrstuhl Mat Verbunde, Kaiserstr 2, D-24143 Kiel, Germany..
    Polonskyi, Oleksandr
    Christian Albrechts Univ Kiel, Inst Mat Wissensch, Lehrstuhl Mat Verbunde, Kaiserstr 2, D-24143 Kiel, Germany..
    Strunskus, Thomas
    Christian Albrechts Univ Kiel, Inst Mat Wissensch, Lehrstuhl Mat Verbunde, Kaiserstr 2, D-24143 Kiel, Germany..
    Faupel, Franz
    Christian Albrechts Univ Kiel, Inst Mat Wissensch, Lehrstuhl Mat Verbunde, Kaiserstr 2, D-24143 Kiel, Germany..
    Stierle, Andreas
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Univ Hamburg, Phys Dept, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibniz Zentrum MLZ, Lichtenbergstr 1, D-85748 Garching, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Correlating Nanostructure, Optical and Electronic Properties of Nanogranular Silver Layers during Polymer-Template-Assisted Sputter Deposition2019In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, no 32, p. 29416-29426Article in journal (Refereed)
    Abstract [en]

    Tailoring the optical and electronic properties of nanostructured polymer-metal composites demonstrates great potential for efficient fabrication of modern organic optical and electronic devices such as flexible sensors, transistors, diodes, or photovoltaics. Self-assembled polymer metal nanocomposites offer an excellent perspective for creating hierarchical nanostructures on macroscopic scales by simple bottom-up processes. We investigate the growth processes of nanogranular silver (Ag) layers on diblock copolymer thin film templates during sputter deposition. The Ag growth is strongly driven by self-assembly and selective wetting on the lamella structure of polystyrene-block-poly (methyl methacrylate). We correlate the emerging nanoscale morphologies with collective optical and electronic properties and quantify the difference in Ag growth on the corresponding homopolymer thin films. Thus, we are able to determine the influence of the respective polymer template and observe substrate effects on the Ag cluster percolation threshold, which affects the insulator-to-metal transition (IMT). Optical spectroscopy in the UV-vis regime reveals localized surface plasmon resonance for the metal polymer composite. Their maximum absorption is observed around the IMT due to the subsequent long-range electron conduction in percolated nanogranular Ag layers. Using X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy, we identify the oxidation of Ag at the acrylate side chains as an essential influencing factor driving the selective wetting behavior in the early growth stages. The results of polymer-templated cluster growth are corroborated by atomic force microscopy and field emission scanning electron microscopy.

  • 35.
    Glier, Tomke E.
    et al.
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Akinsinde, Lewis
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Paufler, Malwin
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Otto, Ferdinand
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Hashemi, Maryam
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Grote, Lukas
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Daams, Lukas
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Neuber, Gerd
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Grimm-Lebsanft, Benjamin
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Biebl, Florian
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Rukser, Dieter
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Lippmann, Milena
    DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Ohm, Wiebke
    DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Schwartzkopf, Matthias
    DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Brett, Calvin
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.
    Matsuyama, Toru
    Max Planck Inst Struct & Dynam Matter, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Ruebhausen, Michael
    Univ Hamburg, Inst Nanostruktur & Festkorperphys, Ctr Free Electron Laser Sci CFEL, Luruper Chaussee 149, D-22761 Hamburg, Germany..
    Functional Printing of Conductive Silver-Nanowire Photopolymer Composites2019In: Scientific Reports, E-ISSN 2045-2322, Vol. 9, article id 6465Article in journal (Refereed)
    Abstract [en]

    We investigated the fabrication and functional behaviour of conductive silver-nanowire-polymer composites for prospective use in printing applications. Silver-nanowires with an aspect ratio of up to 1000 were synthesized using the polyol route and embedded in a UV-curable and printable polymer matrix. Sheet resistances in the composites down to 13 Omega/sq at an optical transmission of about 90% were accomplished. The silver-nanowire composite morphology and network structure was investigated by electron microscopy, atomic force microscopy, profilometry, ellipsometry as well as surface sensitive X-ray scattering. By implementing different printing applications, we demonstrate that our silver nanowires can be used in different polymer composites. On the one hand, we used a tough composite for a 2D-printed film as top contact on a solar cell. On the other hand, a flexible composite was applied for a 3D-printed flexible capacitor.

  • 36.
    Gowda, V. Krishne
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW.
    Rosén, Tomas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. DESY, D-22607 Hamburg, Germany..
    Söderberg, Daniel
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Lundell, Fredrik
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics.
    Nanofibril Alignment during Assembly Revealed by an X-ray Scattering-Based Digital Twin2022In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 16, no 2, p. 2120-2132Article in journal (Refereed)
    Abstract [en]

    The nanostructure, primarily particle orientation, controls mechanical and functional (e.g., mouthfeel, cell compatibility, optical, morphing) properties when macroscopic materials are assembled from nanofibrils. Understanding and controlling the nanostructure is therefore an important key for the continued development of nanotechnology. We merge recent developments in the assembly of biological nanofibrils, X-ray diffraction orientation measurements, and computational fluid dynamics of complex flows. The result is a digital twin, which reveals the complete particle orientation in complex and transient flow situations, in particular the local alignment and spatial variation of the orientation distributions of different length fractions, both along the process and over a specific cross section. The methodology forms a necessary foundation for analysis and optimization of assembly involving anisotropic particles. Furthermore, it provides a bridge between advanced in operandi measurements of nanostructures and phenomena such as transitions between liquid crystal states and in silico studies of particle interactions and agglomeration.

  • 37. Grott, S.
    et al.
    Kotobi, A.
    Reb, L. K.
    Weindl, C. L.
    Guo, R.
    Yin, S.
    Wienhold, K. S.
    Chen, W.
    Ameri, T.
    Schwartzkopf, M.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany.
    Müller-Buschbaum, P.
    Solvent Tuning of the Active Layer Morphology of Non-Fullerene Based Organic Solar Cells2022In: Solar RRL, E-ISSN 2367-198X, Vol. 6, no 6, article id 2101084Article in journal (Refereed)
    Abstract [en]

    Non-fullerene acceptor (NFA)-based organic solar cells have made tremendous progress in recent years. For the neat NFA system PBDB-T:ITIC, the film morphology and crystallinity are tailored by the choice of the solvent used for spin coating the active layers. Three different chlorinated solvents, chlorobenzene (CB), chloroform, and dichlorobenzene, are compared and the obtained active layer morphology is correlated with the optoelectronic properties and the device performance. The small domain sizes in the case of CB are most beneficial for the device performance, whereas the largest number or size of face-on PBDB-T crystallites is not causing the highest power conversion efficiencies (PCEs). In addition, when using CB, the number of edge-on crystallites is highest and the distances between neighboring domains are small. The smoothest blend films are realized with CB, which exhibit correlated roughness with their substrates and no large aggregates have formed in these blend films. Thus, CB offers the best way to balance the aggregation and crystallization kinetics in the active layer and enables the highest PCE values. 

  • 38.
    Guan, Tianfu
    et al.
    Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany..
    Chen, Wei
    Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany.;Shenzhen Technol Univ, Ctr Adv Mat Diagnost Technol, Shenzhen Key Lab Ultraintense Laser & Adv Mat Tech, Shenzhen 518118, Peoples R China.;Shenzhen Technol Univ, Coll Engn Phys, Shenzhen 518118, Peoples R China..
    Tang, Haodong
    Shenzhen Technol Univ, Coll Integrated Circuits & Optoelect Chips, Shenzhen 518118, Peoples R China..
    Li, Dong
    Soochow Univ, Inst Funct Nano & Soft Mat FUNSOM, Jiangsu Key Lab Carbon Based Funct Mat & Devices, Suzhou 215123, Peoples R China..
    Wang, Xiao
    Shenzhen Technol Univ, Ctr Adv Mat Diagnost Technol, Shenzhen Key Lab Ultraintense Laser & Adv Mat Tech, Shenzhen 518118, Peoples R China.;Shenzhen Technol Univ, Coll Engn Phys, Shenzhen 518118, Peoples R China..
    Weindl, Christian L.
    Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany..
    Wang, Yawen
    Soochow Univ, Inst Funct Nano & Soft Mat FUNSOM, Jiangsu Key Lab Carbon Based Funct Mat & Devices, Suzhou 215123, Peoples R China..
    Liang, Zhiqiang
    Soochow Univ, Inst Funct Nano & Soft Mat FUNSOM, Jiangsu Key Lab Carbon Based Funct Mat & Devices, Suzhou 215123, Peoples R China..
    Liang, Suzhe
    Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany..
    Xiao, Tianxiao
    Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany..
    Tu, Suo
    Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser. Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Jiang, Lin
    Soochow Univ, Inst Funct Nano & Soft Mat FUNSOM, Jiangsu Key Lab Carbon Based Funct Mat & Devices, Suzhou 215123, Peoples R China..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zent MLZ, D-85748 Garching, Germany..
    Decoding the Self-Assembly Plasmonic Interface Structure in a PbS Colloidal Quantum Dot Solid for a Photodetector2023In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 17, no 22, p. 23010-23019Article in journal (Refereed)
    Abstract [en]

    Hybrid plasmonic nanostructures have gained enormous attention in a variety of optoelectronic devices due to their surface plasmon resonance properties. Self-assembled hybrid metal/quantum dot (QD) architectures offer a means of coupling the properties of plasmonics and QDs to photodetectors, thereby modifying their functionality. The arrangement and localization of hybrid nanostructures have an impact on exciton trapping and light harvesting. Here, we present a hybrid structure consisting of self-assembled gold nanospheres (Au NSs) embedded in a solid matrix of PbS QDs for mapping the interface structures and the motion of charge carriers. Grazing-incidence small-angle X-ray scattering is utilized to analyze the localization and spacing of the Au NSs within the hybrid structure. Furthermore, by correlating the morphology of the Au NSs in the hybrid structure with the corresponding differences observed in the performance of photodetectors, we are able to determine the impact of interface charge carrier dynamics in the coupling structure. From the perspective of architecture, our study provides insights into the performance improvement of optoelectronic devices.

  • 39.
    Guo, Renjun
    et al.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Han, Dan
    Ludwig Maximilians Univ Munchen, Dept Chem, Munich, Germany..
    Chen, Wei
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany.;Southern Univ Sci & Technol, Dept Elect & Elect Engn, Shenzhen, Peoples R China..
    Dai, Linjie
    Univ Cambridge, Cavendish Lab, Cambridge, England..
    Ji, Kangyu
    Univ Cambridge, Cavendish Lab, Cambridge, England..
    Xiong, Qiu
    Chinese Acad Sci, Fujian Inst Res Struct Matter, Fuzhou, Peoples R China..
    Li, Saisai
    Nankai Univ, Dept Chem, Tianjin, Peoples R China..
    Reb, Lennart K.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Scheel, Manuel A.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Pratap, Shambhavi
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Li, Nian
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Yin, Shanshan
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Xiao, Tianxiao
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Liang, Suzhe
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Oechsle, Anna Lena
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Weindl, Christian L.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany..
    Schwartzkopf, Matthias
    Deutsch Elektronen Synchrotron DESY, Hamburg, Germany..
    Ebert, Hubert
    Ludwig Maximilians Univ Munchen, Dept Chem, Munich, Germany..
    Gao, Peng
    Wang, Kai
    Southern Univ Sci & Technol, Dept Elect & Elect Engn, Shenzhen, Peoples R China.;Chinese Acad Sci, Fujian Inst Res Struct Matter, Fuzhou, Peoples R China..
    Yuan, Mingjian
    Nankai Univ, Dept Chem, Tianjin, Peoples R China..
    Greenham, Neil C.
    Univ Cambridge, Cavendish Lab, Cambridge, England..
    Stranks, Samuel D.
    Univ Cambridge, Cavendish Lab, Cambridge, England..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. Deutsch Elektronen Synchrotron DESY, Hamburg, Germany.;Univ Cambridge, Chem Engn & Biotechnol, Cambridge, England..
    Friend, Richard H.
    Univ Cambridge, Cavendish Lab, Cambridge, England..
    Muller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum, Garching, Germany..
    Degradation mechanisms of perovskite solar cells under vacuum and one atmosphere of nitrogen2021In: Nature Energy, E-ISSN 2058-7546, Vol. 6, no 10, p. 977-+Article in journal (Refereed)
    Abstract [en]

    Extensive studies have focused on improving the operational stability of perovskite solar cells, but few have surveyed the fundamental degradation mechanisms. One aspect overlooked in earlier works is the effect of the atmosphere on device performance during operation. Here we investigate the degradation mechanisms of perovskite solar cells operated under vacuum and under a nitrogen atmosphere using synchrotron radiation-based operando grazing-incidence X-ray scattering methods. Unlike the observations described in previous reports, we find that light-induced phase segregation, lattice shrinkage and morphology deformation occur under vacuum. Under nitrogen, only lattice shrinkage appears during the operation of solar cells, resulting in better device stability. The different behaviour under nitrogen is attributed to a larger energy barrier for lattice distortion and phase segregation. Finally, we find that the migration of excessive PbI2 to the interface between the perovskite and the hole transport layer degrades the performance of devices under vacuum or under nitrogen. Understanding degradation mechanisms in perovskite solar cells is key to their development. Now, Guo et al. show a greater degradation of the perovskite structure and morphology for devices operated under vacuum than under nitrogen.

  • 40.
    Gupta, Pooja
    et al.
    Raja Ramanna Ctr Adv Technol, Indore 452013, India.;Homi Bhabha Natl Inst, Training Sch Complex,Anushakti Nagar, Mumbai 400094, India..
    Srihari, Velaga
    Bhabha Atom Res Ctr, High Pressure & Synchrotron Radiat Phys Div, Mumbai 400085, India..
    Pandit, Pallavi
    DESY, Photon Sci, Notkestr 85, D-22607 Hamburg, Germany..
    Betker, Marie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. DESY, Photon Sci, Notkestr 85, D-22607 Hamburg, Germany..
    Schwartzkopf, Matthias
    DESY, Photon Sci, Notkestr 85, D-22607 Hamburg, Germany..
    Kumar, Dileep
    UGC DAE Consortium Sci Res, Khandwa Rd, Indore 452017, India..
    Dev, Arun Singh
    UGC DAE Consortium Sci Res, Khandwa Rd, Indore 452017, India..
    Bera, Anup Kumar
    UGC DAE Consortium Sci Res, Khandwa Rd, Indore 452017, India..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. DESY, Photon Sci, Notkestr 85, D-22607 Hamburg, Germany..
    Oblique angle deposited FeCo multilayered nanocolumnar structure: Magnetic anisotropy and its thermal stability in polycrystalline thin films2022In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 590, p. 153056-, article id 153056Article in journal (Refereed)
    Abstract [en]

    Iron-Cobalt (FeCo) columnar, multilayered structure is prepared by depositing several thin FeCo layers by varying the angle between the surface normal and the evaporation direction as 0 (normal) and 60(oblique), alternatively. In situ X-ray scattering and magneto-optical Kerr effect (MOKE) measurements established the evolution of magnetic properties with that of the morphology and structure of the multilayer. The strong shape anisotropy and compressive stress of nanocolumns in alternative FeCo layers resulted in a well-defined uniaxial magnetic anisotropy (UMA) with the easy axis of magnetization along the projection of the tilted nanocolumns in the film plane. The stress in the film provides minimization of magnetoelastic energy along the in-plane column direction, which couples with the columnar shape anisotropy energies and results in the preferential orientation of the magnetic easy axis along the oblique angle deposition direction in the film plane. Drastic reduction in the in-plane UMA after annealing at 450 C is attributed to the merging of columns and removal of stresses after heat treatment. The present study opens a new pathway to produce magnetically anisotropic multilayer structures using single material and thus may have prominent implications for future technological devices.

  • 41.
    Hagara, Jakub
    et al.
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Mrkyvkova, Nada
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia.;Slovak Acad Sci, Ctr Adv Mat Applicat, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Feriancova, Lucia
    Comenius Univ, Fac Nat Sci, Ilkovicova 6, Bratislava 84215, Slovakia..
    Putala, Martin
    Comenius Univ, Fac Nat Sci, Ilkovicova 6, Bratislava 84215, Slovakia..
    Nadazdy, Peter
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Hodas, Martin
    Univ Tubingen, Inst Appl Phys, Morgenstelle 10, D-72076 Tubingen, Germany..
    Shaji, Ashin
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Nadazdy, Vojtech
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Huss-Hansen, Mathias K.
    Tech Univ Denmark, Dept Phys, DK-2800 Lyngby, Denmark..
    Knaapila, Matti
    Tech Univ Denmark, Dept Phys, DK-2800 Lyngby, Denmark..
    Hagenlocher, Jan
    Univ Tubingen, Inst Appl Phys, Morgenstelle 10, D-72076 Tubingen, Germany..
    Russegger, Nadine
    Univ Tubingen, Inst Appl Phys, Morgenstelle 10, D-72076 Tubingen, Germany..
    Zwadlo, Matthias
    Univ Tubingen, Inst Appl Phys, Morgenstelle 10, D-72076 Tubingen, Germany..
    Merten, Lena
    Univ Tubingen, Inst Appl Phys, Morgenstelle 10, D-72076 Tubingen, Germany..
    Sojkova, Michaela
    Slovak Acad Sci, Inst Elect Engn, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Hulman, Martin
    Slovak Acad Sci, Inst Elect Engn, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Vlad, Alina
    Synchrotron SOLEIL, F-91190 St Aubin, France..
    Pandit, Pallavi
    DESY, Photon Sci, D-22607 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. DESY, Photon Sci, D-22607 Hamburg, Germany.
    Jergel, Matej
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia.;Slovak Acad Sci, Ctr Adv Mat Applicat, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Majkova, Eva
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia.;Slovak Acad Sci, Ctr Adv Mat Applicat, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Hinderhofer, Alexander
    Univ Tubingen, Inst Appl Phys, Morgenstelle 10, D-72076 Tubingen, Germany..
    Siffalovic, Peter
    Slovak Acad Sci, Inst Phys, Dubravska Cesta 9, Bratislava 84511, Slovakia.;Slovak Acad Sci, Ctr Adv Mat Applicat, Dubravska Cesta 9, Bratislava 84511, Slovakia..
    Schreiber, Frank
    Univ Tubingen, Inst Appl Phys, Morgenstelle 10, D-72076 Tubingen, Germany..
    Novel highly substituted thiophene-based n-type organic semiconductor: structural study, optical anisotropy and molecular control2020In: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 22, no 42, p. 7095-7103Article in journal (Refereed)
    Abstract [en]

    Oligothiophenes and their functionalized derivatives have been shown to be a viable option for high-performance organic electronic devices. The functionalization of oligothiophene-based materials allows further tailoring of their properties for specific applications. We have synthesized a new thiophene-based molecule 1-[5'-(2-naphthyl)-2,2'-bithiophen-5-yl]hexan-1-one (NCOH), and we have studied the optical and structural properties of NCOH thin films. NCOH is a highly substituted member of the oligothiophene family, designed to improve its molecular stacking, where the presence of an electron-withdrawing group enhances its electron transport capabilities. Employing in situ and time-resolved grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements, we determined the NCOH thin film crystallographic structure and its evolution starting from the early stages of the film growth. We observed strong optical anisotropy resulting from a highly oriented crystallographic structure. Additionally, we investigated the substrate-induced changes of the molecular orientation utilizing the few-layer MoS2 with different orientations of the atomic layers. This study, with its primary focus on the fundamentally important n-type molecular semiconductor, contributes to the field of organic-based (opto-)electronics.

  • 42.
    Harder, Constantin
    et al.
    Deutsches Elektronen‐Synchrotron DESY Notkestr. 85 22607 Hamburg Germany;Chair for Functional Materials Department of Physics TUM School of Natural Sciences James‐Franck‐Str. 1 85748 Garching Germany.
    Alexakis, Alexandros Efraim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Bulut, Yusuf
    Deutsches Elektronen‐Synchrotron DESY Notkestr. 85 22607 Hamburg Germany;Chair for Functional Materials Department of Physics TUM School of Natural Sciences James‐Franck‐Str. 1 85748 Garching Germany.
    Xiong, Shuxian
    Deutsches Elektronen‐Synchrotron DESY Notkestr. 85 22607 Hamburg Germany;Chair for Functional Materials Department of Physics TUM School of Natural Sciences James‐Franck‐Str. 1 85748 Garching Germany.
    Sochor, Benedikt
    Deutsches Elektronen‐Synchrotron DESY Notkestr. 85 22607 Hamburg Germany.
    Pan, Guangjiu
    Chair for Functional Materials Department of Physics TUM School of Natural Sciences James‐Franck‐Str. 1 85748 Garching Germany.
    Zhong, Huaying
    Chair for Functional Materials Department of Physics TUM School of Natural Sciences James‐Franck‐Str. 1 85748 Garching Germany.
    Gordeyeva, Korneliya
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Reus, Manuel A.
    Chair for Functional Materials Department of Physics TUM School of Natural Sciences James‐Franck‐Str. 1 85748 Garching Germany.
    Körstgens, Volker
    Chair for Functional Materials Department of Physics TUM School of Natural Sciences James‐Franck‐Str. 1 85748 Garching Germany.
    Jeromin, Arno
    Deutsches Elektronen‐Synchrotron DESY Notkestr. 85 22607 Hamburg Germany;Centre for X‐ray and Nano Science CXNS Deutsches Elektronen‐Synchrotron (DESY) 22607 Hamburg Germany;Department of Physics University of Hamburg Notkestraße 9‐11 22607 Hamburg Germany.
    Keller, Thomas F.
    Deutsches Elektronen‐Synchrotron DESY Notkestr. 85 22607 Hamburg Germany;Centre for X‐ray and Nano Science CXNS Deutsches Elektronen‐Synchrotron (DESY) 22607 Hamburg Germany;Department of Physics University of Hamburg Notkestraße 9‐11 22607 Hamburg Germany.
    Söderberg, L. Daniel
    Department of Fibre and Polymer Technology KTH Royal Institute of Technology Teknikringen 56‐58 10044 Stockholm Sweden;Wallenberg Wood Science Center (WWSC) KTH Royal Institute of Technology Teknikringen 56‐58 Stockholm 10044 Sweden.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Müller‐Buschbaum, Peter
    Chair for Functional Materials Department of Physics TUM School of Natural Sciences James‐Franck‐Str. 1 85748 Garching Germany;Heinz Maier‐Leibnitz‐Zentrum (MLZ) Technische Universität München Lichtenbergstr. 1 85748 Garching Germany.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Deutsches Elektronen‐Synchrotron DESY Notkestr. 85 22607 Hamburg Germany.
    Optical Properties of Slot‐Die Coated Hybrid Colloid/Cellulose‐Nanofibril Thin Films2023In: Advanced Optical Materials, ISSN 2162-7568, E-ISSN 2195-1071, Vol. 11, no 13Article in journal (Refereed)
    Abstract [en]

    Correlating nanostructure and optical properties of thin hybrid films is the crucial ingredient for designing sustainable applications ranging from structural colors in anticounterfeiting to sensors. Here, the tailoring of the refractive index of hybrid cellulose nanofibril/water-dispersed colloidal ink thin films is presented. The authors apply scalable, layer-by-layer slot-die coating for preparing the cellulose nanofibril and hybrid thin films. Making use of the mobility of the polymer chains in the colloids upon annealing, the influence of the different colloid sizes and their glass transition temperature on the refractive index of the hybrid material is shown. The complex refractive indices of the thin films are characterized by spectroscopic ellipsometry and correlated to the different nanostructures of the thin films. The authors find that post-deposition annealing changes the colloidal nanostructure from particulate to agglomerates. Depending on the size of the colloids, imbibition of the colloids into the cellulose nanofibril template is observed. This scalable approach offers new avenues in structural color functional biomaterial hybrid layers.

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  • 43.
    Harder, Constantin
    et al.
    Deutsch Elekt Synchrot DESY, D-22607 Hamburg, Germany.;Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany..
    Betker, Marie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser. Deutsch Elekt Synchrot DESY, D-22607 Hamburg, Germany.
    Alexakis, Alexandros Efraim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Bulut, Yusuf
    Deutsch Elekt Synchrot DESY, D-22607 Hamburg, Germany.;Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany..
    Sochor, Benedikt
    Deutsch Elekt Synchrot DESY, D-22607 Hamburg, Germany..
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Muller-Buschbaum, Peter
    Tech Univ Munich, TUM Sch Nat Sci, Dept Phys, Chair Funct Mat, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zent MLZ, D-85748 Garching, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser. Deutsch Elekt Synchrot DESY, D-22607 Hamburg, Germany.
    Poly(sobrerol methacrylate) Colloidal Inks Sprayed onto Cellulose Nanofibril Thin Films for Anticounterfeiting Applications2024In: ACS Applied Nano Materials, E-ISSN 2574-0970, Vol. 7, no 9, p. 10840-10851Article in journal (Refereed)
    Abstract [en]

    The colloidal layer formation on porous materials is a crucial step for printing and applying functional coatings, which can be used to fabricate anticounterfeiting paper. The deposition of colloidal layers and subsequent thermal treatment allows for modifying the hydrophilicity of the surface of a material. In the present work, wood-based colloidal inks are applied by spray deposition on spray-deposited porous cellulose nanofibrils (CNF) films. The surface modification by thermal annealing of the fabricated colloid-cellulose hybrid thin films is investigated in terms of layering and hydrophobicity. The polymer colloids in the inks are core-shell nanoparticles with different sizes and glass transition temperatures (T-g), thus enabling different and low thermal treatment temperatures. The ratio between the core polymers, poly(sobrerol methacrylate) (PSobMA), and poly(-butyl methacrylate) (PBMA) determines the T-g and hence allows for tailoring of the T-g. The layer formation of the colloidal inks on the porous CNF layer depends on the imbibition properties of the CNF layer which is determined by their morphology. The water adhesion of the CNF layer decreases due to the deposition of the colloids and thermal treatment except for the colloids with a size smaller than the void size of the porous CNF film. In this case, the colloids are imbibed into the CNF layer when T-g of the colloids is reached and the polymer chains transit in a mobile phase. Tailored aggregate and nanoscale-embedded hybrid structures are achieved depending on the colloid properties. The imbibition of these colloids into the porous CNF films is verified with grazing incidence small-angle X-ray scattering. This study shows a route for tuning the nanoscale structure and macroscopic physicochemical properties useful for anticounterfeiting paper.

  • 44. Heger, J. E.
    et al.
    Chen, W.
    Yin, S.
    Li, N.
    Körstgens, V.
    Brett, Calvin
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany.
    Ohm, W.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany.
    Müller-Buschbaum, P.
    Low-Temperature and Water-Based Biotemplating of Nanostructured Foam-Like Titania Films Using ß-Lactoglobulin2022In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 32, no 20, article id 2113080Article in journal (Refereed)
    Abstract [en]

    Given the broad use of nanostructured crystalline titania films, an environmentally friendly and more sustainable synthesis route is highly desirable. Here, a water-based, low-temperature route is presented to synthesize nanostructured foam-like crystalline titania films. A pearl necklace-like nanostructure is introduced as tailored titania morphology via biotemplating with the use of the major bovine whey protein ß-lactoglobulin (ß-lg). It is shown that titania crystallization in a brookite-anatase mixed phase is promoted via spray deposition at a comparatively low temperature of 120 °C. The obtained crystallites have an average grain size of (4.2 ± 0.3) nm. In situ grazing incidence small-angle and wide-angle X-ray scattering (GISAXS/GIWAXS) are simultaneously performed to understand the kinetics of film formation and the templating role of ß-lg during spray coating. In the ß-lg:titania biohybrid composites, the crystal growth in semicrystalline titania clusters is sterically directed by the condensing ß-lg biomatrix. Due to using spray coating, the green chemistry approach to titania-based functional films can be scaled up on a large scale, which can potentially be used in photocatalytic processes or systems related to energy application. 

  • 45.
    Heger, Julian E.
    et al.
    Tech Univ Munich, Chair Funct Mat, TUM Sch Nat Sci, Dept Phys, James Franck Str 1, D-85748 Garching, Germany..
    Chen, Wei
    Tech Univ Munich, Chair Funct Mat, TUM Sch Nat Sci, Dept Phys, James Franck Str 1, D-85748 Garching, Germany.;Shenzhen Technol Univ SZTU, Coll Engn Phys, Lantian Rd 3002, Shenzhen 518118, Peoples R China..
    Zhong, Huaying
    Tech Univ Munich, Chair Funct Mat, TUM Sch Nat Sci, Dept Phys, James Franck Str 1, D-85748 Garching, Germany..
    Xiao, Tianxiao
    Tech Univ Munich, Chair Funct Mat, TUM Sch Nat Sci, Dept Phys, James Franck Str 1, D-85748 Garching, Germany..
    Harder, Constantin
    Tech Univ Munich, Chair Funct Mat, TUM Sch Nat Sci, Dept Phys, James Franck Str 1, D-85748 Garching, Germany.;Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Apfelbeck, Fabian A. C.
    Tech Univ Munich, Chair Funct Mat, TUM Sch Nat Sci, Dept Phys, James Franck Str 1, D-85748 Garching, Germany..
    Weinzierl, Alexander F.
    Tech Univ Munich, Chair Funct Mat, TUM Sch Nat Sci, Dept Phys, James Franck Str 1, D-85748 Garching, Germany..
    Boldt, Regine
    Leibniz Inst Polymerforsch Dresden eV, Inst Polymerwerkstoffe, Hohe Str 6, D-01069 Dresden, Germany..
    Schraa, Lucas
    Leibniz Inst Polymerforsch Dresden eV, Inst Polymerwerkstoffe, Hohe Str 6, D-01069 Dresden, Germany..
    Euchler, Eric
    Leibniz Inst Polymerforsch Dresden eV, Inst Polymerwerkstoffe, Hohe Str 6, D-01069 Dresden, Germany..
    Sambale, Anna K.
    Leibniz Inst Polymerforsch Dresden eV, Inst Polymerwerkstoffe, Hohe Str 6, D-01069 Dresden, Germany..
    Schneider, Konrad
    Leibniz Inst Polymerforsch Dresden eV, Inst Polymerwerkstoffe, Hohe Str 6, D-01069 Dresden, Germany..
    Schwartzkopf, Matthias
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Mueller-Buschbaum, P.
    Tech Univ Munich, Chair Funct Mat, TUM Sch Nat Sci, Dept Phys, James Franck Str 1, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zent MLZ, Lichtenbergstr 1, D-85748 Garching, Germany..
    Superlattice deformation in quantum dot films on flexible substrates via uniaxial strain2023In: Nanoscale Horizons, ISSN 2055-6764, E-ISSN 2055-6756, Vol. 8, no 3, p. 383-395Article in journal (Refereed)
    Abstract [en]

    The superlattice in a quantum dot (QD) film on a flexible substrate deformed by uniaxial strain shows a phase transition in unit cell symmetry. With increasing uniaxial strain, the QD superlattice unit cell changes from tetragonal to cubic to tetragonal phase as measured with in situ grazing-incidence small-angle X-ray scattering (GISAXS). The respective changes in the optoelectronic coupling are probed with photoluminescence (PL) measurements. The PL emission intensity follows the phase transition due to the resulting changing inter-dot distances. The changes in PL intensity accompany a redshift in the emission spectrum, which agrees with the Forster resonance energy transfer (FRET) theory. The results are essential for a fundamental understanding of the impact of strain on the performance of flexible devices based on QD films, such as wearable electronics and next-generation solar cells on flexible substrates.

  • 46. Heindl, M. W.
    et al.
    Kodalle, T.
    Fehn, N.
    Reb, L. K.
    Liu, S.
    Harder, C.
    Abdelsamie, M.
    Eyre, L.
    Sharp, I. D.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Müller-Buschbaum, P.
    Kartouzian, A.
    Sutter-Fella, C. M.
    Deschler, F.
    Strong Induced Circular Dichroism in a Hybrid Lead-Halide Semiconductor Using Chiral Amino Acids for Crystallite Surface Functionalization2022In: Advanced Optical Materials, ISSN 2162-7568, E-ISSN 2195-1071, Vol. 10, no 14, p. 2200204-, article id 2200204Article in journal (Refereed)
    Abstract [en]

    Chirality is a desired property in functional semiconductors for optoelectronic, catalytic, and spintronic applications. Here, introducing enantiomerically-pure 3-aminobutyric acid (3-ABA) into thin films of the 1D semiconductor dimethylammonium lead iodide (DMAPbI3) is found to result in strong circular dichroism (CD) in the optical absorption. X-ray diffraction and grazing incidence small angle X-ray scattering (GISAXS) are applied to gain molecular-scale insights into the chirality transfer mechanism, which is attributed to a chiral surface modification of DMAPbI3 crystallites. This study demonstrates that the CD signal strength can be controlled by the amino-acid content relative to the crystallite surface area. The CD intensity is tuned by the composition of the precursor solution and the spin-coating time, thereby achieving anisotropy factors (gabs) as high as 1.75 × 10–2. Grazing incidence wide angle scattering reveals strong preferential ordering that can be suppressed via tailored synthesis conditions. Different contributions to the chiroptical properties are resolved by a detailed analysis of the CD signal utilizing an approach based on the Mueller matrix model. This report of a novel class of chiral hybrid semiconductors with precise control over their optical activity presents a promising approach for the design of circularly polarized light detectors and emitters.

  • 47. Hohn, N.
    et al.
    Schlosser, S. J.
    Bießmann, L.
    Grott, S.
    Xia, S.
    Wang, K.
    Schwartzkopf, M.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. Deutsches Elektronen-Synchrotron, Germany.
    Müller-Buschbaum, P.
    Readily available titania nanostructuring routines based on mobility and polarity controlled phase separation of an amphiphilic diblock copolymer2018In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 10, no 11, p. 5325-5334Article in journal (Refereed)
    Abstract [en]

    The amphiphilic diblock copolymer polystyrene-block-polyethylene oxide is combined with sol-gel chemistry to control the structure formation of blade-coated foam-like titania thin films. The influence of evaporation time before immersion into a poor solvent bath and polarity of the poor solvent bath are studied. Resulting morphological changes are quantified by scanning electron microscopy (SEM) and grazing incidence small angle X-ray scattering (GISAXS) measurements. SEM images surface structures while GISAXS accesses inner film structures. Due to the correlation of evaporation time and mobility of the polymer template during the phase separation process, a decrease in the distances of neighboring titania nanostructures from 50 nm to 22 nm is achieved. Furthermore, through an increase of polarity of an immersion bath the energetic incompatibility of the hydrophobic block and the solvent can be enhanced, leading to an increase of titania nanostructure distances from 35 nm to 55 nm. Thus, a simple approach is presented to control titania nanostructure in foam-like films prepared via blade coating, which enables an easy upscaling of film preparation.

  • 48.
    Hohn, Nuri
    et al.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Hetzenecker, Andreas E.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Giebel, Michael A.
    Tech Univ Munich, Dept Chem, Lehrstuhl Anorgan Chem Schwerpunkt Neue Mat, Lichtenbergstr 4, D-85747 Garching, Germany..
    Geier, Sebastian
    Tech Univ Munich, Dept Chem, Lehrstuhl Anorgan Chem Schwerpunkt Neue Mat, Lichtenbergstr 4, D-85747 Garching, Germany..
    Biessmann, Lorenz
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Koerstgens, Volker
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Saxena, Nitin
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Schlipf, Johannes
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Ohm, Wiebke
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Deimel, Peter S.
    Tech Univ Munich, Phys Dept, Lehrstuhl Mol Nanowissensch & Chem Phys Grenzflac, James Franck Str 1, D-85748 Garching, Germany..
    Allegretti, Francesco
    Tech Univ Munich, Phys Dept, Lehrstuhl Mol Nanowissensch & Chem Phys Grenzflac, James Franck Str 1, D-85748 Garching, Germany..
    Barth, Johannes V.
    Tech Univ Munich, Phys Dept, Lehrstuhl Mol Nanowissensch & Chem Phys Grenzflac, James Franck Str 1, D-85748 Garching, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Faessler, Thomas F.
    Tech Univ Munich, Dept Chem, Lehrstuhl Anorgan Chem Schwerpunkt Neue Mat, Lichtenbergstr 4, D-85747 Garching, Germany..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, Lichtenbergstr 1, D-85748 Garching, Germany..
    Amphiphilic diblock copolymer-mediated structure control in nanoporous germanium-based thin films2019In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 11, no 4, p. 2048-2055Article in journal (Refereed)
    Abstract [en]

    Fabrication of porous, foam-like germanium-based (Ge-based) nanostructures is achieved with the use of the amphiphilic diblock copolymer polystyrene-b-polyethylene oxide as structure directing agent. Basic concepts of block copolymer assisted sol-gel synthesis are successfully realized based on the [Ge-9](4-) Zintl clusters as a precursor for Ge-based thin films. Material/elemental composition and crystalline Ge-based phases are investigated via X-ray photoelectron spectroscopy and X-ray diffraction measurements, respectively. Poor-good solvent pair induced phase separation leads to pore sizes in the Ge-based films up to 40 nm, which can be tuned through a change of the molar mixing ratio between polymer template and precursor as proven by grazing incidence small angle X-ray scattering and scanning electron microscopy.

  • 49.
    Hohn, Nuri
    et al.
    Tech Univ Munich, Lehrstuhl Funkt Mat, Dept Phys, James Franck Str 1, D-85748 Garching, Germany. chwartzkopf, Matthias; Roth, Stephan V..
    Shlosser, Steffen J.
    Biessmann, Lorenz
    Song, Lin
    Grott, Sebastian
    Xia, Senlin
    Wang, Kun
    Schwartzkopf, Matthias
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Mueller-Buschbaum, Peter
    Impact of Catalytic Additive on Spray Deposited and Nanoporous Titania in Films Observed via in Situ X-ray Scattering: Implications for hanced Photovoltaics2018In: ACS Applied Nano Materials, ISSN 2574-0970, Vol. 1, no 8, p. 4227-4235Article in journal (Refereed)
    Abstract [en]

    With the aim of obtaining nanostructured titania thin films for the tential use in hybrid or dye sensitized solar cells, the amphiphilic block copolymer polystyrene-b-poly(ethylene oxide) is employed as a ructure directing template in combination with solgel chemistry. For sy upscaling, spraying is used as a deposition technique. In situ azing incidence small-angle X-ray scattering (GISAXS) measurements are rformed during spraying and show that most titania structures are ready formed within the solution prior to deposition. However, ructural rearrangement is enabled during the deposition period when all amounts of hydrochloric acid (HCl) are used as a catalytic ditive to the spray solution. This behavior is ascribed to an altering the reaction dynamics and phase separation in the presence of HCl, ich significantly improves the templating effect of the employed block copolymer. With HCl as an additive the final nanoscale rphologies exhibit smaller pore sizes and strongly enhanced order as mpared to thin films sprayed from solutions that do not contain HCl as antified with atomic force microscopy, scanning electron microscopy, d GISAXS.

  • 50. Jatav, H.
    et al.
    Shabaninezhad, M.
    Mičetić, M.
    Chakravorty, A.
    Mishra, A.
    Schwartzkopf, M.
    Chumakov, A.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Kabiraj, D.
    A Combinatorial Study Investigating the Growth of Ultrasmall Embedded Silver Nanoparticles upon Thermal Annealing2022In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 38, no 39, p. 11983-11993Article in journal (Refereed)
    Abstract [en]

    Ultrasmall nanoparticles (NPs) with a high active surface area are essential for optoelectronic and photovoltaic applications. However, the structural stability and sustainability of these ultrasmall NPs at higher temperatures remain a critical problem. Here, we have synthesized the nanocomposites (NCs) of Ag NPs inside the silica matrix using the atom beam co-sputtering technique. The post-deposition growth of the embedded Ag NPs is systematically investigated at a wide range of annealing temperatures (ATs). A novel, fast, and effective procedure, correlating the experimental (UV-vis absorption results) and theoretical (quantum mechanical modeling, QMM) results, is used to estimate the size of NPs. The QMM-based simulation, employed for this work, is found to be more accurate in reproducing the absorption spectra over the classical/modified Drude model, which fails to predict the expected shift in the LSPR for ultrasmall NPs. Unlike the classical Drude model, the QMM incorporates the intraband transition of the conduction band electrons to calculate the effective dielectric function of metallic NCs, which is the major contribution of LSPR shifts for ultrasmall NPs. In this framework, a direct comparison is made between experimentally and theoretically observed LSPR peak positions, and it is observed that the size of NPs grows from 3 to 18 nm as AT increases from room temperature to 900 °C. Further, in situ grazing-incidence small- & wide-angle X-ray scattering and transmission electron microscopy measurements are employed to comprehend the growth of Ag NPs and validate the UV + QMM results. We demonstrate that, unlike chemically grown NPs, the embedded Ag NPs ensure greater stability in size and remain in an ultrasmall regime up to 800 °C, and beyond this temperature, the size of NPs increases exponentially due to dominant Ostwald ripening. Finally, a three-stage mechanism is discussed to understand the process of nucleation and growth of the silica-embedded Ag NPs. 

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