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  • 1.
    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)
  • 2.
    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: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal (Other academic)
  • 3. 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.

  • 4.
    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)
  • 5.
    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.

  • 6.
    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, ISSN 2045-2322, 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.

  • 7.
    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.

  • 8.
    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.

  • 9.
    Kousal, Jaroslav
    et al.
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Shelemin, Artem
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Schwartzkopf, Matthias
    Deutsches Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Polonskyi, Oleksandr
    Univ Kiel, Chair Multicomponent Mat, Fac Engn, Kiel, Germany..
    Hanus, Jan
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Solar, Pavel
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Vaidulych, Mykhailo
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Nikitin, Daniil
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Pleskunov, Pavel
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Krtous, Zdenek
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Strunskus, Thomas
    Univ Kiel, Chair Multicomponent Mat, Fac Engn, Kiel, Germany..
    Faupel, Franz
    Univ Kiel, Chair Multicomponent Mat, Fac Engn, Kiel, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsches Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Biederman, Hynek
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Choukourov, Andrei
    Charles Univ Prague, Dept Macromol Phys, Fac Math & Phys, V Holesovickach 2, Prague 18000, Czech Republic..
    Magnetron-sputtered copper nanoparticles: lost in gas aggregation and found by in situ X-ray scattering2018In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 10, no 38, p. 18275-18281Article in journal (Refereed)
    Abstract [en]

    Magnetron discharge in a cold buffer gas represents a liquid-free approach to the synthesis of metal nanoparticles (NPs) with tailored structure, chemical composition and size. Despite a large number of metal NPs that were successfully produced by this method, the knowledge of the mechanisms of their nucleation and growth in the discharge is still limited, mainly because of the lack of in situ experimental data. In this work, we present the results of in situ Small Angle X-ray Scattering measurements performed in the vicinity of a Cu magnetron target with Ar used as a buffer gas. Condensation of atomic metal vapours is found to occur mainly at several mm distance from the target plane. The NPs are found to be captured preferentially within a region circumscribed by the magnetron plasma ring. In this capture zone, the NPs grow to the size of 90 nm whereas smaller ones sized 10-20 nm may escape and constitute a NP beam. Time-resolved measurements of the discharge indicate that the electrostatic force acting on the charged NPs may be largely responsible for their capturing nearby the magnetron.

  • 10. Ohm, Wiebke
    et al.
    Rothkirch, Andre
    Pandit, Pallavi
    Koerstgens, Volker
    Mueller-Buschbaum, Peter
    Rojas, Ramiro
    Yu, Shun
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Brett, Calvin J.
    Soderberg, Daniel L.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Morphological properties of airbrush spray-deposited enzymatic cellulose thin films2018In: JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, ISSN 1945-9645, Vol. 15, no 4, p. 759-769Article in journal (Refereed)
    Abstract [en]

    We investigate the layer formation of enzymatic cellulose by airbrush spray coating on silicon oxide surfaces. The layer structure and morphology of enzymatic cellulose films in the thickness range between 86 nm and 2.1 A mu m is determined as a function of the spray coating procedures. For each spray coating step, layer buildup, surface topography, crystallinity as well as the nanoscale structure are probed with atomic force microscopy and surface-sensitive X-ray scattering methods. Without intermittent drying, the film thickness saturates; with intermittent drying, a linear increase in layer thickness with the number of spray pulses is observed. A closed cellulose layer was always observed. The crystallinity remains unchanged; the nanoscale structures show three distinct sizes. Our results indicate that the smallest building blocks increasingly contribute to the morphology inside the cellulose network for thicker films, showing the importance of tailoring the cellulose nanofibrils. For a layer-by-layer coating, intermittent drying is mandatory.

  • 11.
    Ohm, Wiebke
    et al.
    DESY, Hamburg, Germany..
    Rothkirch, Andre
    DESY, Hamburg, Germany..
    Pandit, Pallavi
    DESY, Hamburg, Germany..
    Koerstgens, Volker
    Tech Univ Munich, Garching, Germany..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Garching, Germany..
    Rojas, Ramiro
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Yu, Shun
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Brett, Calvin
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.
    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..
    Morphological and crystalline properties of airbrush spray-deposited enzymatic cellulose thin films2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 12.
    Rosén, Tomas
    et al.
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. SUNY Stony Brook.
    Brouzet, Christophe
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Mechanics.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. DESY.
    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), Mechanics.
    Söderberg, Daniel
    KTH, School of Engineering Sciences (SCI), Mechanics. 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.
    Three-Dimensional Orientation of Nanofibrils in Axially Symmetric Systems Using Small-Angle X-ray Scattering2018In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 122, no 12, p. 6889-6899Article in journal (Refereed)
    Abstract [en]

    The increased availability and brilliance of new X-ray facilities have in the recent years opened up the possibility to characterize the alignment of dispersed anisotropic nanoparticles in various microfluidic applications, from hydrodynamic self-assemblies to flows in complex geometries. In such applications, it is vital to study the alignment of the nanoparticles in the flow, as this in turn affects the final properties of the self-assembled superstructures or those of the flow itself. Small-angle X-ray scattering (SAXS) is a well-suited characterization technique for this but typically provides the alignment in a projected plane perpendicular to the beam direction. In this work, we demonstrate a simple method to reconstruct the full three-dimensional orientation distribution function from a SAXS experiment through the assumption that the azimuthal angle of the nanoparticles around the flow direction is distributed uniformly, an assumption that is valid for a large range of nanoparticle flow processes. For demonstration purposes, the experimental results from previous works on hydrodynamic self-assembly of cellulose nanofibrils (CNFs) into filaments have been revised, resulting in a small correction to the presented order parameters. The results are then directly compared with simple numerical models to describe the increased alignment of CNFs both in the flowing system and during the drying of the filament. The proposed reconstruction method will allow for further improvements of theoretical or numerical simulations and consequently open up new possibilities for optimizing assembly processes, which include flow alignment of elongated nanoparticles.

  • 13. Schwartzkopf, Matthias
    et al.
    Roth, Stephan V.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Investigating Polymer-Metal Interfaces by Grazing Incidence Small-Angle X-Ray Scattering from Gradients to Real-Time Studies2016In: NANOMATERIALS, ISSN 2079-4991, Vol. 6, no 12, article id 239Article, review/survey (Refereed)
    Abstract [en]

    Tailoring the polymer-metal interface is crucial for advanced material design. Vacuum deposition methods for metal layer coating are widely used in industry and research. They allow for installing a variety of nanostructures, often making use of the selective interaction of the metal atoms with the underlying polymer thin film. The polymer thin film may eventually be nanostructured, too, in order to create a hierarchy in length scales. Grazing incidence X-ray scattering is an advanced method to characterize and investigate polymer-metal interfaces. Being non-destructive and yielding statistically relevant results, it allows for deducing the detailed polymer-metal interaction. We review the use of grazing incidence X-ray scattering to elucidate the polymer-metal interface, making use of the modern synchrotron radiation facilities, allowing for very local studies via in situ (so-called stop-sputter) experiments as well as studies observing the nanostructured metal nanoparticle layer growth in real time.

  • 14.
    Song, Lin
    et al.
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Wang, Weijia
    Northwestern Polytech Univ, Sch Mat Sci & Engn, State Key Lab Solidificat Proc, Youyixilu 127, Xian 710072, Shaanxi, Peoples R China..
    Barabino, Edoardo
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Yang, Dan
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Koerstgens, Volker
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Zhang, Peng
    Deutsch Elektronen Synchrotron DESY, Photon Sci, 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, Photon Sci, Notkestr 85, D-22607 Hamburg, Germany..
    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..
    Composition Morphology Correlation in PTB7-Th/PC71 BM Blend Films for Organic Solar Cells2019In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, no 3, p. 3125-3135Article in journal (Refereed)
    Abstract [en]

    From a morphological perspective, the understanding of the influence of the [6,6]-phenyl C-71-butyric acid methyl ester (PC71BM) content on the morphology of the active layer is not complete in organic solar cells (OSCs) with bulk heterojunction (BHJ) configuration based on the low-bandgap polymer poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo [1,2-b:4,5-b dithiophene-2,6-diyhalt-(4-(2-ethylhexyl)-3-fluorothieno [3,4-b]thiophene-)-2-carboxylate-2-6-diyl] (PTB7-Th). In this work, we obtain the highest power conversion efficiency (PCE) of 10.5% for BHJ organic solar cells (OSCs) with a PTB7-Th/PC71BM weight ratio of 1:1.5. To understand the differences in PCEs caused by the PC71BM content, we investigate the morphology of PTB7-Th/PC71BM blend films in detail by determining the domain sizes, the polymer crystal structure, optical properties, and vertical composition as a function of the PC71BM concentration. The surface morphology is examined with atomic force microscopy, and the inner film morphology is probed with grazing incidence small angle X-ray scattering. The PTB7-Th crystal structure is characterized with grazing incidence wide-angle X-ray scattering and UV/vis spectroscopy. X-ray reflectivity is employed to yield information about the film vertical composition. The results show that in PTB7-Th/PC71BM blend films, the increase of PC71BM content leads to an enhanced microphase separation and a decreased polymer crystallinity. Moreover, a high PC71BM concentration is found to decrease the polymer domain sizes and crystal sizes and to promote polymer conjugation length and formation of fullerene-rich and/or polymer-rich layers. The differences in photovoltaic performance are well explained by these findings.

  • 15. Song, Lin
    et al.
    Wang, Weijia
    Koerstgens, Volker
    Gonzalez, Daniel Mosegui
    Loehrer, Franziska C.
    Schaffer, Christoph J.
    Schlipf, Johannes
    Peters, Kristina
    Bein, Thomas
    Fattakhova-Rohlfing, Dina
    Roth, Stephan V.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. Photon Science, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
    Mueller-Buschbaum, Peter
    In situ study of spray deposited titania photoanodes for scalable fabrication of solid-state dye-sensitized solar cells2017In: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 40, p. 317-326Article in journal (Refereed)
    Abstract [en]

    Spray coating, a cost-effective and scalable technique, has been employed for fabricating titania films for solidstate dye-sensitized solar cells (ssDSSCs). The spray deposition of films is inherently based on kinetic processes with great complexity, which poses great challenges in its understanding. In the present work, the kinetics of the structure evolution of deposited films are investigated by in situ grazing-incidence small-angle x-ray scattering during spray deposition. The spray-solution is prepared via a polystyrene-block-polyethylene oxide (PS-b-PEO) template assisted sol-gel synthesis. It is turned into nanostructured titania/PS-b-PEO composite films via spray deposition. The information about nanostructure length scales of the composite film is obtained in real-time and in situ, revealing the morphological evolution during the spray deposition. The resulting mesoporous titania films serve as photoanodes of ssDSSCs, which couple with the solution-cast hole transport layer to form the active layers. The well working ssDSSCs demonstrate the successful use of spray deposition as a large-scale manufacturing process for photoanodes.

  • 16. Su, Bo
    et al.
    Caller-Guanan, Herbert A.
    Koerstgens, Volker
    Rui, Yichuan
    Yao, Yuan
    Saxena, Nitin
    Santoro, Gonzalo
    Roth, Stephan V.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. Deutsch Elektronen Synchrotron DESY, Germany.
    Mueller-Buschbaum, Peter
    Macroscale and Nanoscale Morphology Evolution during in Situ Spray Coating of Titania Films for Perovskite Solar Cells2017In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 9, no 50, p. 43724-43732Article in journal (Refereed)
    Abstract [en]

    Mesoporous titania is a cheap and widely used material for photovoltaic applications. To enable a large-scale fabrication and a controllable pore size, we combined a block copolymer-assisted sol gel route with spray coating to fabricate titania films, in which the block copolymer polystyrene-block-poly(ethylene oxide) (PS-b-PEO) is used as a structure-directing template. Both the macroscale and nanoscale are studied. The kinetics and thermodynamics of the spray deposition processes are simulated on a macroscale, which shows a good agreement with the large-scale morphology of the spray-coated films obtained in practice. On the nanoscale, the structure evolution of the titania films is probed with in situ grazing incidence small-angle X-ray scattering (GISAXS) during the spray process. The changes of the PS domain size depend not "only on micellization but also on solvent evaporation during the spray coating. Perovskite (CH3NH3PbI3) solar cells (PSCs) based on sprayed titania film are fabricated, which showcases the suitability of spray-deposited titania films for PSCs.

  • 17. Vayalil, Sarathlal Koyiloth
    et al.
    Gupta, Ajay
    Roth, Stephan V.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. DESY, Germany.
    Study of pattern transition in nanopatterned Si(100) produced by impurity-assisted low-energy ion-beam erosion2017In: Applied Physics A: Materials Science & Processing, ISSN 0947-8396, E-ISSN 1432-0630, Vol. 123, no 4, article id 225Article in journal (Refereed)
    Abstract [en]

    In this work, formation of self-organized Si nanostructures induced by pure Fe incorporation during normal incidence low-energy (1keV) Ar+ ion bombardment is presented. It has been observed that the incorporation of Fe affects the evolution of the surface topography. The addition of Fe generates pronounced nanopatterns, such as dots, ripples and combinations of dots and ripples. The orientation of the ripple wave vector of the patterns formed is found to be in a direction normal to the Fe flow. The nanoripples with wavelength of the order of 39 nm produced is expected to be the lowest wavelength of the patterns reported on ion-beam-eroded structures under the incorporation of metallic impurities as per our knowledge. From the AFM and GISAXS analysis, it has been confirmed that the ripples formed are asymmetric in nature. The effect of the concentration of the Fe on morphological transition of the patterns has been studied using Rutherford backscattering measurements.

  • 18. Wang, K.
    et al.
    Körstgens, V.
    Yang, D.
    Hohn, N.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
    Müller-Buschbaum, P.
    Morphology control of low temperature fabricated ZnO nanostructures for transparent active layers in all solid-state dye-sensitized solar cells2018In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, no 10, p. 4405-4415Article in journal (Refereed)
    Abstract [en]

    Based on a method using sol-gel chemistry combined with diblock copolymer templating, a low-temperature route to fabricate zinc oxide (ZnO) films with tunable morphologies including foam-like, worm-like and sphere-like structures is demonstrated. The morphologies are probed using scanning electron microscopy and grazing-incidence small-angle X-ray scattering. Based on controlled nanostructured ZnO films, all solid-state dye-sensitized solar cells (ssDSSCs) are prepared, for which every layer is deposited at low temperature to reduce the energy consumption of the manufacturing process. Transparent active layers for ssDSSCs are obtained, which demonstrates the possibility for building integrated solar cells. The ssDSSCs with a worm-like ZnO morphology, exhibiting relatively better ordered interconnected three-dimensional structures and larger meso-pore sizes, show the highest power conversion efficiencies and almost 100% efficiency of charge separation and collection for the absorbed photons. After 120 days, almost 80% of the initial power conversion efficiency is maintained in ambient air conditions, which demonstrates good long-term stability of the ssDSSCs even without special encapsulation. 

  • 19.
    Wang, Kun
    et al.
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Biessmann, Lorenz
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Schwartzkopf, Matthias
    Deutsch Elektronen Synchrontron DESY, Notkestr 85, D-22603 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsch Elektronen Synchrontron DESY, Notkestr 85, D-22603 Hamburg, Germany.
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Tuning of the Morphology and Optoelectronic Properties of ZnO/P3HT/P3HT-b-PEO Hybrid Films via Spray Deposition Method2018In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 10, no 24, p. 20569-20577Article in journal (Refereed)
    Abstract [en]

    The self-assembly of amphiphilic diblock copolymers yields the possibility of using them as a template for tailoring the film morphologies of solgel chemistry-derived inorganic electron transport materials, such as mesoporous ZnO and TiO2. However, additional steps including etching and backfilling are required for the common bulk heterojunction fabrication process when using insulating diblock copolymers. Here, we use the conducting diblock copolymer poly(3-hexylthiophene)-block-poly(ethylene oxide) (P3HT-b-PEO) in which P3HT acts as charge carrier transport material and light absorber, whereas PEO serves as a template for ZnO synthesis. The initial solution is subsequently spray-coated to obtain the hybrid film. Scanning electron microscopy and grazing-incidence small-angle X-ray scattering measurements reveal a significant change in the morphology of the hybrid films during deposition. Optoelectronic properties illustrate the improved charge separation and charge transfer process. Both the amount of the diblock copolymer and the annealing temperature play an important role in tuning the morphology and the optoelectronic properties. Hybrid films being sprayed from a solution with the ratio of omega(ZnO), omega(P3HT), and omega(P3HT-b-PEO) of 2:1:1 and subsequent annealing at 80 degrees C show the most promising morphology combined with an optimal photoluminescence quenching. Thus, the presented simple, reagent- and energy-saving fabrication method provides a promising approach for a large-scale preparation of bulk heterojunction P3HT/ZnO films on flexible substrates.

  • 20.
    Wang, Kun
    et al.
    Tech Univ Munich, Dept Phys, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany. .
    Xia, Senlin
    Cao, Wei
    Hohn, Nuri
    Grott, Sebastian
    Kreuzer, Lucas P.
    Schwartzkopf, Matthias
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsch Elektronen Synchrontron DESY, Notkestr 85, D-22603 Hamburg, Germany.
    Mueller-Buschbaum, Peter
    Comparison of UV Irradiation and Sintering on Mesoporous Spongelike ZnO lms Prepared from PS-b-P4VP Templated Sol-Gel Synthesis2018In: ACS Applied Nano Materials, ISSN 2574-0970, Vol. 1, no 12, p. 7139-7148Article in journal (Refereed)
    Abstract [en]

    Mesoporous ZnO films with large surface-area-to-volume ratio show great omise in multiple applications, among which solid-state dye-sensitized lar cells (ssDSSCs) have attracted great attention in the field of otovoltaics. An appropriate mesopore size in the nanostructured ZnO lms significantly plays an indispensable role in improving the device ficiency that resulted from an efficient penetration of dye molecules d solid hole transport material. In the present work, mesoporous ongelike ZnO films are prepared using sol-gel synthesis templated by a block copolymer polystyrene-block-poly(4-vinylpyridine). Two different mplate removal techniques, ultraviolet (UV) irradiation and gh-temperature sintering, are used to compare their respective impact the pore sizes of the final ZnO thin films. Both the surface rphology and the inner morphology show that mesopores obtained via UV radiation are smaller as compared to their sintered counterparts. reover, increasing the template-to-ZnO precursor ratio is found to rther enlarge present mesopores. Accordingly, a strong correlation tween the pore sizes of sol-gel synthesized ZnO films and photovoltaic rformance of fabricated ssDSSCs is demonstrated. In contrast with the vices fabricated from the UV-irradiated ZnO films, those obtained from ntered samples show >2 times higher efficiency.

  • 21. Wang, W.
    et al.
    Widmann, T.
    Song, L.
    Fröschl, T.
    Hüsing, N.
    Mo, G.
    Wu, Z.
    Zhang, P.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Fan, H.
    Müller-Buschbaum, P.
    Aging of low-temperature derived highly flexible nanostructured TiO 2 /P3HT hybrid films during bending2019In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 7, no 17, p. 10805-10814Article in journal (Refereed)
    Abstract [en]

    To meet the demand for low-cost, lightweight, portable and building-integrated solar cells, developing flexible and cost-efficient photo-active hybrid films is of significant interest. In this work, we investigate the mechanical properties of hybrid layers consisting of mesoporous TiO 2 filled with poly(3-hexylthiophene-2,5-diyl) (P3HT) as a function of the number of bending cycles. The TiO 2 /P3HT layers are deposited on flexible PET substrates at low temperatures (≤140 °C), which is beneficial for reducing the processing energy input and in turn lowering the production costs. Non-filled and partially filled mesoporous titania films are studied for comparison. The surface morphology is examined with scanning electron microscopy (SEM) before and after the bending tests. The inner film morphology is characterized with grazing incidence small-angle X-ray scattering (GISAXS). Based on the observed morphology, micromechanical models are used to analyze the mechanical properties of the investigated films. The results show that the TiO 2 /P3HT layers have a low elastic modulus and P3HT helps to stabilize the titania nanostructures against fracture. The SEM observations are well explained with the established models in a quantitative way.

  • 22.
    Xia, Senlin
    et al.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funktionelle Mat, Garching, Germany..
    Song, Lin
    Tech Univ Munich, Phys Dept, Lehrstuhl Funktionelle Mat, Garching, Germany.;Northwestern Polytech Univ, Inst Flexible Elect, West Youyi Rd 127, Xian 710072, Shaanxi, Peoples R China..
    Chen, Wei
    Tech Univ Munich, Phys Dept, Lehrstuhl Funktionelle Mat, Garching, Germany..
    Koerstgens, Volker
    Tech Univ Munich, Phys Dept, Lehrstuhl Funktionelle Mat, Garching, Germany..
    Opel, Matthias
    Bayer Akad Wissensch, Walther Meissner Inst, Walther Meissner Str 8, D-85748 Garching, Germany..
    Schwartzkopf, Matthias
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22603 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funktionelle Mat, Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, Lichtenbergstr 1, D-85748 Garching, Germany..
    Printed Thin Diblock Copolymer Films with Dense Magnetic Nanostructure2019In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, no 24, p. 21935-21945Article in journal (Refereed)
    Abstract [en]

    Thin hybrid films with dense magnetic structures for sensor applications are printed using diblock copolymer (DBC) templating magnetic nanoparticles (MNPs). To achieve a high-density magnetic structure, the printing ink is prepared by mixing polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) with a large PS volume fraction and PS selective MNPs. Solvent vapor annealing is applied to generate a parallel cylindrical film morphology (with respect to the substrate), in which the MNP-residing PS domains are well separated by the PMMA matrix, and thus, the formation of large MNP agglomerates is avoided. Moreover, the morphologies of the printed thin films are determined as a function of the MNP concentration with real and reciprocal space characterization techniques. The PS domains are found to be saturated with MNPs at 1 wt %, at which the structural order of the hybrid films reaches a maximum within the studied range of MNP concentration. As a beneficial aspect, the MNP loading improves the morphological order of the thin DBC films. The dense magnetic structure endows the thin films with a faster superparamagnetic responsive behavior, as compared to thick films where identical MNPs are used, but dispersed inside the minority domains of the DBC.

  • 23.
    Xia, Senlin
    et al.
    Tech Univ Munich, Dept Phys, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Song, Lin
    Tech Univ Munich, Dept Phys, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Hohn, Nuri
    Tech Univ Munich, Dept Phys, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Wang, Kun
    Tech Univ Munich, Dept Phys, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Grott, Sebastian
    Tech Univ Munich, Dept Phys, Lehrstuhl Funkt Mat, James Franck Str 1, D-85748 Garching, Germany..
    Opel, Matthias
    Bayer Akad Wissensch, Walther Meissner Inst, Walther Meissner Str 8, D-85748 Garching, Germany..
    Schwartzkopf, Matthias
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22603 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-22603 Hamburg, Germany..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Dept Phys, 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..
    Spray-Coating Magnetic Thin Hybrid Films of PS-b-PNIPAM and Magnetite Nanoparticles2019In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 29, no 15, article id 1808427Article in journal (Refereed)
    Abstract [en]

    Spray coating is employed to fabricate magnetic thin films composed of the diblock copolymer polystyrene-block-poly(N-isopropylacrylamide) and Fe3O4 magnetic nanoparticles (MNPs) functionalized with hydrophobic coatings. The kinetics of structure formation of the hybrid films is followed in situ with grazing incidence small angle X-ray scattering during the spray deposition. To gain a better understanding of the influence of MNPs on the overall structure formation, the pure polymer film is also deposited as a reference via an identical spray protocol. At the initial spraying stage, the hybrid film (containing 2 wt% of MNPs) exhibits a faster formation process of a complete film as compared to the reference. The existence of MNPs depresses the dewetting behavior of polymer films on the substrate at macroscale and simultaneously alters the polymer microphase separation structure orientation from parallel to vertical. As spraying proceeds, MNPs aggregate into agglomerates with increasing sizes. After the spray deposition is finished, both samples gradually reach an equilibrium state and magnetic films with stable structures are achieved in the end. Superconducting quantum interference device investigation reveals the superparamagnetic property of the sprayed hybrid film. Consequently, potential application of sprayed films in fields such as magnetic sensors or data storage appears highly promising.

  • 24.
    Xia, Senlin
    et al.
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Song, Lin
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Koerstgens, Volker
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Opel, Matthias
    Bayerische Akad Wissensch, Walther Meissner Inst, Walther Meissner Str 8, D-85748 Garching, Germany..
    Schwartzkopf, Matthias
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22603 Hamburg, 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-22603 Hamburg, Germany.
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Lehrstuhl Funkt Mat, Phys Dept, James Franck Str 1, D-85748 Garching, Germany..
    Magnetic nanoparticle-containing soft-hard diblock copolymer films with high order2018In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 10, no 25, p. 11930-11941Article in journal (Refereed)
    Abstract [en]

    For sensor applications, superparamagnetic anisotropy is an indispensable property, which is typically achieved by employing an external field to guide the arrangement of magnetic nanoparticles (NPs). In the present investigation, the diblock copolymer polystyrene-block-poly(N-isopropylacrylamide) (PS-b-PNIPAM) is printed as a template to localize magnetic iron oxide NPs without any external field. Via microphase separation, cylindrical nanostructures of PS in a PNIPAM matrix are obtained, aligned perpendicular to the substrate. Since the magnetite NPs (Fe3O4) are functionalized with hydrophobic organic chains showing affinity to the PS blocks, they can selectively aggregate inside the PS cylinders. Moreover, solvent vapor annealing allows the achievement of nanostructures inside the hybrid system with a very high order, even at a high NP loading. Therefore, NPs can accumulate within PS domains to form perpendicularly aligned aggregates with high periodicity. The magnetic properties of the hybrid films are determined at various temperatures in two orthogonal directions (with PS cylinders vertical and parallel to the applied magnetic field). All hybrid films show superparamagnetism and a remarkable magnetic anisotropy is achieved at certain NP concentrations. This investigation shows a facile route to prepare superparamagnetic films with magnetic anisotropy and offers a novel possibility to future magnetic sensor fabrication.

  • 25.
    Zhong, Qi
    et al.
    Zhejiang Sci Tech Univ, Natl Base Int Sci & Technol Cooperat Text & Consu, Engn Res Ctr Ecodyeing & Finishing Text, Key Lab Adv Text Mat & Mfg Technol,Minist Educ, Hangzhou 310018, Zhejiang, Peoples R China.;Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat Fachgebiet Phys Weicher Mat, James Franck Str 1, D-85748 Garching, Germany..
    Mi, Lei
    Zhejiang Sci Tech Univ, Natl Base Int Sci & Technol Cooperat Text & Consu, Engn Res Ctr Ecodyeing & Finishing Text, Key Lab Adv Text Mat & Mfg Technol,Minist Educ, Hangzhou 310018, Zhejiang, Peoples R China..
    Metwalli, Ezzeldin
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat Fachgebiet Phys Weicher Mat, James Franck Str 1, D-85748 Garching, Germany..
    Biessmann, Lorenz
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat Fachgebiet Phys Weicher Mat, James Franck Str 1, D-85748 Garching, Germany..
    Philipp, Martine
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat Fachgebiet Phys Weicher Mat, James Franck Str 1, D-85748 Garching, Germany..
    Miasnikova, Anna
    Univ Potsdam, Inst Chem, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany..
    Laschewsky, Andre
    Univ Potsdam, Inst Chem, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany.;Fraunhofer Inst Angew Polymerforschung, Geiselbergstr 69, D-14476 Potsdam, Germany..
    Papadakis, Christine M.
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat Fachgebiet Phys Weicher Mat, James Franck Str 1, D-85748 Garching, Germany..
    Cubitt, Robert
    Inst Laue Langevin, 6 Rue Jules Horowitz, F-38000 Grenoble, France..
    Schwartzkopf, Matthias
    Deutsch Elektronen Synchrotron DESY, Photon Sci, Notkestr 85, D-22607 Hamburg, Germany..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Wang, Jiping
    Zhejiang Sci Tech Univ, Natl Base Int Sci & Technol Cooperat Text & Consu, Engn Res Ctr Ecodyeing & Finishing Text, Key Lab Adv Text Mat & Mfg Technol,Minist Educ, Hangzhou 310018, Zhejiang, Peoples R China..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Mat Fachgebiet Phys Weicher Mat, James Franck Str 1, D-85748 Garching, Germany..
    Effect of chain architecture on the swelling and thermal response of star-shaped thermo-responsive (poly(methoxy diethylene glycol acrylate)-block-polystyrene)(3) block copolymer films2018In: Soft Matter, ISSN 1744-683X, E-ISSN 1744-6848, Vol. 14, no 31, p. 6582-6594Article in journal (Refereed)
    Abstract [en]

    The effect of chain architecture on the swelling and thermal response of thin films obtained from an amphiphilic three-arm star-shaped thermo-responsive block copolymer poly(methoxy diethylene glycol acrylate)-block-polystyrene ((PMDEGA-b-PS)(3)) is investigated by in situ neutron reflectivity (NR) measurements. The PMDEGA and PS blocks are micro-phase separated with randomly distributed PS nanodomains. The (PMDEGA-b-PS)(3) films show a transition temperature (TT) at 33 degrees C in white light interferometry. The swelling capability of the (PMDEGA-b-PS)(3) films in a D2O vapor atmosphere is better than that of films from linear PS-b-PMDEGA-b-PS triblock copolymers, which can be attributed to the hydrophilic end groups and limited size of the PS blocks in (PMDEGA-b-PS)(3). However, the swelling kinetics of the as-prepared (PMDEGA-b-PS)(3) films and the response of the swollen film to a temperature change above the TT are significantly slower than that in the PS-b-PMDEGA-b-PS films, which may be related to the conformation restriction by the star-shape. Unlike in the PS-b-PMDEGA-b-PS films, the amount of residual D2O in the collapsed (PMDEGA-b-PS)(3) films depends on the final temperature. It decreases from (9.7 +/- 0.3)% to (7.0 +/- 0.3)% or (6.0 +/- 0.3)% when the final temperatures are set to 35 degrees C, 45 degrees C and 50 degrees C, respectively. This temperature-dependent reduction of embedded D2O originates from the hindrance of chain conformation from the star-shaped chain architecture.

1 - 25 of 25
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  • asciidoc
  • rtf