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  • 501.
    Zhang, Fan
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Pan, Jinshan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Recent Development of Corrosion Protection Strategy Based on Mussel Adhesive Protein2019In: FRONTIERS IN MATERIALS, ISSN 2296-8016, Vol. 6, article id 207Article, review/survey (Refereed)
    Abstract [en]

    Many of traditional anti-corrosion approaches using chromate are effective but hazardous to natural environment and human health, so development of green and effective alternatives is desirable. One of the mussel adhesive proteins derived from mussel byssus presents extraordinary adhesion to steel surface and exhibits film-forming and corrosion inhibition properties. Novel strategies for enhancing the corrosion inhibition of steel by the protein have been demonstrated recently. The protein together with ceria nanoparticles presents a great potential for the development of new corrosion inhibitors and thin films that are "green" and "effective," and have "smart" protection properties.

  • 502.
    Zhang, Fuguo
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Cong, Jiayan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Li, Yuanyuan
    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.
    Bergstrand, Jan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Liu, Haichun
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Cai, Bin
    State Key Laboratory of Fine Chemicals, Dalian University of Technology (DUT).
    Hajian, Alireza
    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.
    Yao, Zhaoyang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Wang, Linqin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Hao, Yan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Yang, Xichuan
    State Key Laboratory of Fine Chemicals, Dalian University of Technology (DUT).
    Gardner, James M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Ågren, Hans
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Widengren, Jerker
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Kloo, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. State Key Laboratory of Fine Chemicals, Dalian University of Technology (DUT).
    A facile route to grain morphology controllable perovskite thin films towards highly efficient perovskite solar cells2018In: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 53, p. 405-414Article in journal (Refereed)
    Abstract [en]

    Perovskite photovoltaics have recently attracted extensive attention due to their unprecedented high power conversion efficiencies (PCEs) in combination with primitive manufacturing conditions. However, the inherent polycrystalline nature of perovskite films renders an exceptional density of structural defects, especially at the grain boundaries (GBs) and film surfaces, representing a key challenge that impedes the further performance improvement of perovskite solar cells (PSCs) and large solar module ambitions towards commercialization. Here, a novel strategy is presented utilizing a simple ethylammonium chloride (EACl) additive in combination with a facile solvent bathing approach to achieve high quality methyammonium lead iodide (MAPbI3) films. Well-oriented, micron-sized grains were observed, which contribute to an extended carrier lifetime and reduced trap density. Further investigations unraveled the distinctively prominent effects of EACl in modulating the perovskite film quality. The EACl was found to promote the perovskite grain growing without undergoing the formation of intermediate phases. Moreover, the EACl was also revealed to deplete at relative low temperature to enhance the film quality without compromising the beneficial bandgap for solar cell applications. This new strategy boosts the power conversion efficiency (PCE) to 20.9% and 19.0% for devices with effective areas of 0.126 cm2 and 1.020 cm2, respectively, with negligible current hysteresis and enhanced stability. Besides, perovskite films with a size of 10 × 10 cm2, and an assembled 16 cm2(5 × 5 cm2 module) perovskite solar module with a PCE of over 11% were constructed.

  • 503.
    Zhang, Jinbao
    et al.
    Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia..
    Daniel, Quentin
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Zhang, Tian
    Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia..
    Wen, Xiaoming
    Swinburne Univ Technol, Ctr Microphoton, Melbourne, Vic 3122, Australia..
    Xu, Bo
    Uppsala Univ, Phys Chem, Dept Chem, Angstrom Lab, Box 523, S-75120 Uppsala, Sweden..
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Dalian Univ Technol, State Key Lab Fine Chem, DUT KTH Joint Educ & Res Ctr Mol Devices, Dalian 116012, Peoples R China..
    Bach, Udo
    Monash Univ, Dept Chem Engn, Clayton, Vic 3800, Australia.;CSIRO Mfg, Clayton, Vic 3168, Australia.;Melbourne Ctr Nanofabricat, Clayton, Vic 3800, Australia..
    Cheng, Yi-Bing
    Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia.;Wuhan Univ Technol, State Key Lab Silicate Mat Architectures, Wuhan 430070, Hubei, Peoples R China..
    Chemical Dopant Engineering in Hole Transport Layers for Efficient Perovskite Solar Cells: Insight into the Interfacial Recombination2018In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 12, no 10, p. 10452-10462Article in journal (Refereed)
    Abstract [en]

    Chemical doping of organic semiconductors has been recognized as an effective way to enhance the electrical conductivity. In perovskite solar cells (PSCs), various types of dopants have been developed for organic hole transport materials (HTMs); however, the knowledge of the basic requirements for being efficient dopants as well as the comprehensive roles of the dopants in PSCs has not been clearly revealed. Here, three copper-based complexes with controlled redox activities are applied as dopants in PSCs, and it is found that the oxidative reactivity of dopants presents substantial impacts on conductivity, charge dynamics, and solar cell performance. A significant improvement of open- circuit voltage (V-oc) by more than 100 mV and an increase of power conversion efficiency from 13.2 to 19.3% have been achieved by tuning the doping level of the HTM. The observed large variation of V-oc for three dopants reveals their different recombination kinetics at the perovskite/HTM interfaces and suggests a model of an interfacial recombination mechanism. We also suggest that the dopants in HTMs can also affect the charge recombination kinetics as well as the solar cell performance. Based on these findings, a strategy is proposed to physically passivate the electron- hole recombination by inserting an ultrathin Al2O3 insulating layer between the perovskite and the HTM. This strategy contributes a significant enhancement of the power conversion efficiency and environmental stability, indicating that dopant engineering is one crucial way to further improve the performance of PSCs.

  • 504.
    Zhang, Li
    et al.
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Yang, Xichuan
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Wang, Weihan
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Gurzadyan, Gagik G.
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Li, Jiajia
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Li, Xiaoxin
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    An, Jincheng
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Yu, Ze
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Wang, Haoxin
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Cai, Bin
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Hagfeldt, Anders
    Ecole Polytech Fed Lausanne, Lab Photomol Sci, Inst Chem Sci & Engn, CH-1015 Lausanne, Switzerland..
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China.
    13.6% Efficient Organic Dye-Sensitized Solar Cells by Minimizing Energy Losses of the Excited State2019In: ACS ENERGY LETTERS, ISSN 2380-8195, Vol. 4, no 4, p. 943-951Article in journal (Refereed)
    Abstract [en]

    The electron-injection energy losses of dye-sensitized solar cells (DSSCs) are among the fundamental problems hindering their successful breakthrough application. Two triazatruxene (TAT)-based sensitizers, with one containing a flexible Z-type double bond and another a rigid single bond, coded as ZL001 and ZL003, respectively, have been synthesized and applied in DSSCs to probe the energy losses in the process of electron injection. Using time-resolved laser spectroscopic techniques in the kinetic study, ZL003 with the rigid single bond promotes much faster electron injection into the conductive band of TiO2 especially in the locally excited state (hot injection), which leads to higher electron density in TiO2 and a higher V-oc. The devices based on ZL003 exhibited a champion power conversion efficiency (PCE) of 13.6% with V-oc = 956 mV, J(sc) = 20.73 mA cm(-2), and FF = 68.5%, which are among the highest recorded results to date on single dye-sensitized DSSCs. An independent certified PCE of 12.4% has been obtained for devices based on ZL003.

  • 505.
    Zhang, Liang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology. VINNOVA Competence Ctr Adv Bioprod Continuous Pro, AdBIOPRO, Stockholm, Sweden..
    Castan, Andreas
    GE Healthcare Biosci AB, Bjorkgatan 30, S-75184 Uppsala, Sweden..
    Stevenson, Joanne
    Cobra Biol AB, Stockholm, Sweden..
    Chatzissavidou, Nathalie
    Cobra Biol AB, Stockholm, Sweden..
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience.
    Chotteau, Veronique
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology. VINNOVA Competence Ctr Adv Bioprod Continuous Pro, AdBIOPRO, Stockholm, Sweden..
    Combined effects of glycosylation precursors and lactate on the glycoprofile of IgG produced by CHO cells2019In: Journal of Biotechnology, ISSN 0168-1656, E-ISSN 1873-4863, Vol. 289, p. 71-79Article in journal (Refereed)
    Abstract [en]

    The glycosylation profile of therapeutic monoclonal antibodies (mAbs) is a crucial quality parameter for industrial Immunoglobulin G (IgG) production. Several alternative carbon sources, which function as glycosylation precursors, have been reported to impact the glycosylation pattern. Since the cells give priority to glucose uptake, the presence of this substrate can lower the effects of alternative sugars on the glycosylation. In order to get a better understanding of the influence of alternative sugars on the glycosylation and to investigate how they impact each other, combinations of mannose, fructose, galactose and fucose were fed to Chinese hamster ovary (CHO) cells in batch culture when the glucose became depleted and the lactate, accumulated in the culture, was used as carbon source. Feeding with a feed containing mannose or glucose decreased by 3-7% the percentage of high mannose glycans compared to a feed without mannose or glucose. Feeding with a feed containing galactose led to 8-20% increase of monogalactoglycans (G1) glycans and 2-6% rise of digalactoglycans (G2) glycans compared to feeding without galactose or glucose. The cells fed with fucose exhibited a significantly higher concentration of intracellular GDP-Fucose. This work indicates that a feeding strategy based on non-glucose sugars and potentially lactate, could be adopted to obtain a targeted glycosylation profile.

  • 506.
    Zhang, Liang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Wang, MingLiang
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Decision and Control Systems (Automatic Control).
    Castan, Andreas
    Stevenson, Joanne
    Chatzissavidou, Nathalie
    Hjalmarsson, Håkan
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Decision and Control Systems (Automatic Control).
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience.
    Chotteau, Véronique
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology. AdBIOPRO, VINNOVA Competence Centre for Advanced Bioproduction by Continuous Processing, KTH, Sweden.
    Glycan Residues Balance Analysis: A novel model for the N-linked glycosylation of IgG produced by CHO cells.2020In: Metabolic engineering, ISSN 1096-7176, E-ISSN 1096-7184, Vol. 57, p. 118-128Article in journal (Refereed)
    Abstract [en]

    The structure of N-linked glycosylation is a very important quality attribute for therapeutic monoclonal antibodies. Different carbon sources in cell culture media, such as mannose and galactose, have been reported to have different influences on the glycosylation patterns. Accurate prediction and control of the glycosylation profile are important for the process development of mammalian cell cultures. In this study, a mathematical model, that we named Glycan Residues Balance Analysis (GReBA), was developed based on the concept of Elementary Flux Mode (EFM), and used to predict the glycosylation profile for steady state cell cultures. Experiments were carried out in pseudo-perfusion cultivation of antibody producing Chinese Hamster Ovary (CHO) cells with various concentrations and combinations of glucose, mannose and galactose. Cultivation of CHO cells with mannose or the combinations of mannose and galactose resulted in decreased lactate and ammonium production, and more matured glycosylation patterns compared to the cultures with glucose. Furthermore, the growth rate and IgG productivity were similar in all the conditions. When the cells were cultured with galactose alone, lactate was fed as well to be used as complementary carbon source, leading to cell growth rate and IgG productivity comparable to feeding the other sugars. The data of the glycoprofiles were used for training the model, and then to simulate the glycosylation changes with varying the concentrations of mannose and galactose. In this study we showed that the GReBA model had a good predictive capacity of the N-linked glycosylation. The GReBA can be used as a guidance for development of glycoprotein cultivation processes.

  • 507.
    Zhang, Peili
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Li, L.
    Nordlund, D.
    Chen, Hong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Fan, Lizhou
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Zhang, Biaobiao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sheng, Xia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Daniel, Quentin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Dendritic core-shell nickel-iron-copper metal/metal oxide electrode for efficient electrocatalytic water oxidation2018In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 9, no 1, article id 381Article in journal (Refereed)
    Abstract [en]

    Electrochemical water splitting requires efficient water oxidation catalysts to accelerate the sluggish kinetics of water oxidation reaction. Here, we report a promisingly dendritic core-shell nickel-iron-copper metal/metal oxide electrode, prepared via dealloying with an electrodeposited nickel-iron-copper alloy as a precursor, as the catalyst for water oxidation. The as-prepared core-shell nickel-iron-copper electrode is characterized with porous oxide shells and metallic cores. This tri-metal-based core-shell nickel-iron-copper electrode exhibits a remarkable activity toward water oxidation in alkaline medium with an overpotential of only 180 mV at a current density of 10 mA cm-2. The core-shell NiFeCu electrode exhibits pH-dependent oxygen evolution reaction activity on the reversible hydrogen electrode scale, suggesting that non-concerted proton-electron transfers participate in catalyzing the oxygen evolution reaction. To the best of our knowledge, the as-fabricated core-shell nickel-iron-copper is one of the most promising oxygen evolution catalysts.

  • 508.
    Zhang, Peili
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, DUT-KTH Joint Education and Research Centre on Molecular Devices, Dalian University of Technology, Dalian, 116024, China.
    Sheng, Xia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, DUT-KTH Joint Education and Research Centre on Molecular Devices, Dalian University of Technology, Dalian, 116024, China.
    Chen, Xiaoyu
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Fang, Zhiyong
    Jiang, Jian
    Wang, Mei
    Li, Fusheng
    Fan, Lizhou
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Ren, Yansong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Zhang, Biaobiao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Timmer, Brian J. J.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Ahlquist, Mårten S. G.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, DUT-KTH Joint Education and Research Centre on Molecular Devices, Dalian University of Technology, Dalian, 116024, China.
    Paired Electrocatalytic Oxygenation and Hydrogenation of Organic Substrates with Water as the Oxygen and Hydrogen Source2019In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 58, no 27, p. 9155-9159Article in journal (Refereed)
    Abstract [en]

    The use of water as an oxygen and hydrogen source for the paired oxygenation and hydrogenation of organic substrates to produce valuable chemicals is of utmost importance as a means of establishing green chemical syntheses. Inspired by the active Ni3+ intermediates involved in electro-catalytic water oxidation by nickel-based materials, we prepared NiBx as a catalyst and used water as the oxygen source for the oxygenation of various organic compounds. NiBx was further employed as both an anode and a cathode in a paired electrosynthesis cell for the respective oxygenation and hydrogenation of organic compounds, with water as both the oxygen and hydrogen source. Conversion efficiency and selectivity of >= 99% were observed during the oxygenation of 5-hydroxy-methylfurfural to 2,5-furandicarboxylic acid and the simultaneous hydrogenation of p-nitrophenol to p-aminophenol. This paired electrosynthesis cell has also been coupled to a solar cell as a stand-alone reactor in response to sunlight.

  • 509.
    Zhang, Wei
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Functional Materials for Perovskite Solar Cells2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Energy plays a significant role in our daily lives, but most energy provided by fossil fuels causes serious environmental problems including air pollution, global warming, and ecological damage. In addition, it has been estimated that all of our fossil fuels will run out in 2088 and thus it is highly important to study and apply renewable energy sources. Among all the alternatives, solar energy is clean, sustainable, and abundant. It is estimated that the amount of power from the sun that strikes the earth in 90 minutes is more than the entire world consumes in one year. The perovskite solar cell (PSC) is one of the strongest tools to utilize solar energy because of its high power conversion efficiency and easy fabrication process. However, the lead that is normally used in the perovskite layer is considered harmful to the environment and to human health. Moreover, the low conductivity and hole mobility of the hole-transport material (HTM) Spiro-OMeTAD and the low overall device stability against humidity are all issues that might hinder the further development of PSC technology. This thesis concerns all of these aspects, with a general focus on different functional materials.

    The aim of this thesis was to develop environmentally friendly and low-cost functional materials in order to solve existing problems while at the same time revealing insights into carrier transport, molecular doping, and surface passivation.

    In Chapter 1 and Chapter 2, the current status of PSCs and the experimental and theoretical methods used in this thesis are presented.

    In Chapter 3, the properties of coordination complexes, including molybdenum clusters and polyiodide-linked gold complexes, and their potential application in solar cells as lead-free light absorbers are discussed.

    In Chapter 4, the synthesis of four coordination complexes with different metal cores and ligands and their application as HTMs in PSCs is discussed. Their oxidation potential, hole mobility, conductivity, and packing methods are presented.

    In Chapter 5, two p-type dopants – Cu(bpcm)2 and (MeO-TPD)TFSI – are introduced for the organic HTM Spiro-OMeTAD. Both of these could significantly increase the conductivity of Spiro-OMeTAD films. In addition, (MeO-TPD)TFSI could work separately without hygroscopic LiTFSI at high doping amounts thus potentially increasing the device’s stability. The structure of oxidized Spiro-OMeTAD on the base of the Spiro(TFSI)2 is also discussed.

    In Chapter 6, density functional theory modeling of four different functional groups – including amino (−NH2), phosphine (−PH2), hydroxyl (−OH), and thiol (−SH) groups – in combination with polyhedral oligomeric silsesquioxane is discussed in terms of estimating the adsorption energy with respect to different perovskite surface models. The amino functional group showed the strongest adsorption energy and was further compared with the thiol group in experiments.

  • 510.
    Zhang, Wei
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Organic Salts as p-Type Dopants for Efficient LiTFSI-free Perovskite Solar CellsManuscript (preprint) (Other academic)
    Abstract [en]

    Despite the ubiquity and importance of organic hole-transport materials in photovoltaic devices, their intrinsic low conductivity remains a drawback. Thus, chemical doping forms an indispensable solution always required. The most widely used p-type dopant, FK209, is a cobalt coordination complex. By reducing Co(III) to Co(II), Spiro-OMeTAD becomes partially oxidized and the film conductivity is initially increased. To further increase the conductivity, the hygroscopic co-dopant LiTFSI is typically needed. However, lithium salts are normally quite hygroscopic, and thus water absorption has been suggested as a significant reason for perovskite degradation and therefore limited device stability. In this work, we report a LiTFSI-free doping process by applying organic salts in relatively high amounts. Film conductivity and morphology are studied at different doping amounts. The resulting solar cell devices show comparable power conversion efficiencies (PCEs) as those based on conventional LiTFSI-doped Spiro-OMeTAD but considerably better long-term device stability in ambient atmosphere.

  • 511.
    Zhang, Wei
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Hua, Yong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Wang, Linqin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Zhang, Biaobiao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Li, Yuanyuan
    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.
    Liu, Peng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Leandri, Valentina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Guo, Yu
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Chen, Hong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Gardner, James M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Dalian Univ Technol DUT, DUT KTH Joint Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Kloo, Lars
    The Central Role of Ligand Conjugation for Properties of Coordination Complexes as Hole-Transport Materials in Perovskite Solar Cells2019In: ACS APPLIED ENERGY MATERIALS, ISSN 2574-0962, Vol. 2, no 9, p. 6768-6779Article in journal (Refereed)
    Abstract [en]

    Two zinc-based coordination complexes Y3 and Y4 have been synthesized and characterized, and their performance as hole-transport materials (HTMs) for perovskite solar cells (PSCs) has been investigated. The complex Y3 contains two separate ligands, and the molecular structure can be seen as a disconnected porphyrin ring. On the other hand, Y4 consists of a porphyrin core and therefore is a more extended conjugated system as compared to Y3. The optical and redox properties of the two different molecular complexes are comparable. However, the hole mobility and conductivity of Y4 as macroscopic material are remarkably higher than that of Y3. Furthermore, when employed as hole-transport materials in perovskite solar cells, cells containing Y4 show a power conversion efficiency (PCE) of 16.05%, comparable to the Spiro-OMeTAD-based solar cells with an efficiency around 17.08%. In contrast, solar cells based on Y3 show a negligible efficiency of about 0.01%. The difference in performance of Y3 and Y4 is analyzed and can be attributed to the difference in packing of the nonplanar and planar building blocks in the corresponding materials.

  • 512.
    Zhang, Wei
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Sadollahkhani, Azar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Li, Yuanyuan
    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.
    Leandri, Valentina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Gardner, James M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Mechanistic Insights from Functional Group Exchange Surface Passivation: A Combined Theoretical and Experimental Study2019In: ACS APPLIED ENERGY MATERIALS, ISSN 2574-0962, Vol. 2, no 4, p. 2723-2733Article in journal (Refereed)
    Abstract [en]

    Four different functional groups including amino (-NH2), phosphine (-PH2), hydroxyl (-OH), and thiol (-SH) were combined with POSS (polyhedral oligomeric silsesquioxane) molecules to investigate how functional groups affect the surface passivation of POSS systems. Results from density-functional theory (DFT) calculations indicate that functional group amino (-NH2) with adsorption energy 86 (56) kJ mol(-1) is consistently better than that of thiol (-SH) with adsorption energy 68 (43) kJ mor(-1) for different passivation mechanisms. Theoretical studies on the analogous POSS-OH and POSS-PH2 systems show similar adsorption energies. Two of the systems were also investigated experimentally; aminopropyl isobutyl POSS (POSS-NH2) and mercaptopropyl isobutyl POSS (POSS-SH) were applied as passivation materials for MAPbI(3) (MA = methylammonium) perovskite and (FA)(0.85)(MA)(0.15)Pb(I-3)(0.85)(Br-3)(0)(.15)(FA = formamidinium) perovskite films. The same conclusion was drawn based on the results from contact angle studies, X-ray diffraction (XRD), and the stability of solar cells in ambient atmosphere, indicating the vital importance of choice of functional groups for passivation of the perovskite materials.

  • 513.
    Zhang, Wei
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Wang, Linqin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Guo, Yu
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Zhang, Biaobiao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Leandri, Valentina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Xu, Bo
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Li, Zhuofeng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Gardner, James M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Kloo, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Single crystal structure and opto-electronic properties of oxidized Spiro-OMeTAD2020In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 56, no 10, p. 1589-1592Article in journal (Refereed)
    Abstract [en]

    Single crystals of Spiro(TFSI)2 were grown, the optical and electronic properties were characterized and compared with neutral Spiro-OMeTAD. Density-functional theory was used to get insights into binding and band structure properties. The flat valence bands indicate a rather limited orbital overlap in Spiro(TFSI)2.

  • 514.
    Zhang, Xian
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. Wuhan Univ Sci & Technol, State Key Lab Refractory Mat & Met, Hubei Prov Key Lab Syst Sci Met Proc, Int Res Inst Steel Technol, Wuhan 430081, Hubei, Peoples R China..
    Odnevall Wallinder, Inger
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Leygraf, Christopher
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Atmospheric corrosion of Zn-Al coatings in a simulated automotive environment2018In: Surface Engineering, ISSN 0267-0844, E-ISSN 1743-2944, Vol. 34, no 9, p. 641-648Article in journal (Refereed)
    Abstract [en]

    Accelerated NVDA (VDA 233-102) tests were performed on bare Zn and Al sheets, Galfan coating (Zn-5 wt-% Al) and Galvalume coating (Zn-55 wt-% Al) on steel. ZnO, Zn(OH)(2) and Zn-5(OH)(8)Cl-2 center dot H2O were the main corrosion products identified on both bare Zn sheet and Galfan. AlOOH and Al(OH)(3) were preferentially formed on bare Al sheet and Galvalume. In addition, Zn-Al-containing corrosion products, Zn6Al2(OH)(16)CO3 center dot 4H(2)O and/or Zn2Al(OH)(6)Cl center dot 2H(2)O were identified on both Galfan and Galvalume. Corrosion products of Zn6Al2(OH)(16)CO3 center dot 4H(2)O with a platelet morphology were preferentially formed in the zinc-rich interdendritic regions of the Galvalume surface. Galfan revealed a similar corrosion behaviour as bare Zn sheet, whereas Galvalume exhibited similar behaviour as bare Al sheet. Deposition of chlorides highly influenced the corrosion of both Galvalume and Al rather than Galfan and Zn due to the rapid local damage of the compact native thin film of Al2O3.

  • 515.
    Zhang, Xiaoliang
    et al.
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Cappel, Ute B.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Jia, Donglin
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Zhou, Qisen
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Du, Juan
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Sloboda, Tamara
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Svanström, Sebastian
    Uppsala Univ, Dept Phys & Astron, Div Mol & Condensed Matter Phys, Box 516, SE-75120 Uppsala, Sweden..
    Johansson, Fredrik O. L.
    Uppsala Univ, Dept Phys & Astron, Div Mol & Condensed Matter Phys, Box 516, SE-75120 Uppsala, Sweden..
    Lindblad, Andreas
    Uppsala Univ, Dept Phys & Astron, Div Mol & Condensed Matter Phys, Box 516, SE-75120 Uppsala, Sweden..
    Giangrisostomi, Erika
    Helmholtz Zentrum Berlin GmbH, Inst Methods & Instrumentat Synchrotron Radiat Re, Albert Einstein Str 15, D-12489 Berlin, Germany..
    Ovsyannikov, Ruslan
    Helmholtz Zentrum Berlin GmbH, Inst Methods & Instrumentat Synchrotron Radiat Re, Albert Einstein Str 15, D-12489 Berlin, Germany..
    Liu, Jianhua
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Rensmo, Håkan
    Uppsala Univ, Dept Phys & Astron, Div Mol & Condensed Matter Phys, Box 516, SE-75120 Uppsala, Sweden..
    Gardner, James M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Johansson, Erik M. J.
    Uppsala Univ, Phys Chem, Dept Chem Angstrom, S-75120 Uppsala, Sweden..
    Probing and Controlling Surface Passivation of PbS Quantum Dot Solid for Improved Performance of Infrared Absorbing Solar Cells2019In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 31, no 11, p. 4081-4091Article in journal (Refereed)
    Abstract [en]

    Surface properties of colloidal quantum dots (CQDs) are critical for the transportation and recombination of the photoinduced charge carrier in CQD solar cells, therefore dominating the photovoltaic performance. Herein, PbS CQD passivated using liquid-state ligand exchange (LSLX) and solid-state ligand exchange (SSLX) strategies are in detail investigated using photoelectron spectroscopy (PES), and solar cell devices are prepared to understand the link between the CQD surface properties and the solar cell function. PES using different energies in the soft and hard Xray regime is applied to study the surface and bulk properties of the CQDs, and the results show more effective surface passivation of the CQDs prepared with the LSLX strategy and less formation of lead-oxide. The CQD solar cells prepared with LSLX strategy show higher performance, and the photoelectric measurements suggest that the recombination of photoinduced charges is reduced for the solar cell prepared with the LSLX approach. Meanwhile, the fabricated solar cells exhibit good stability. This work provides important insights into how to fine-tune the CQD surface properties by improving the CQD passivation, and how this is linked to further improvements of the device photovoltaic performance.

  • 516.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Xie, Sheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Yan, Mingdi
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Ramström, Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Enzyme- and ruthenium-catalyzed dynamic kinetic resolution involving cascade alkoxycarbonylations for asymmetric synthesis of 5-Substituted N-Aryloxazolidinones2019In: Molecular Catalysis, ISSN 2468-8231, Vol. 470, p. 138-144Article in journal (Refereed)
    Abstract [en]

    AAsymmetric synthesis of N-aryloxazolidinones via dynamic kinetic resolution was developed. A ruthenium-based catalyst was used in the racemization of beta-anilino alcohols, while Candida antarctica lipase B (CAL-B) was applied for two selective alkoxycarbonylations operating in cascade. Various N-aryloxazolidinone derivatives were obtained in high yields and good enantiopurities.

  • 517.
    Zhang, Yongfei
    et al.
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, Dalian 116024, Peoples R China..
    Liang, Yongqi
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, Dalian 116024, Peoples R China..
    Wang, Yajuan
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, Dalian 116024, Peoples R China..
    Guo, Fengwan
    Peking Univ, Beijing Natl Lab Mol Sci, State Key Lab Struct Chem Unstable & Stable Speci, Coll Chem & Mol Engn, Beijing 100871, Peoples R China..
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Xu, Dongsheng
    Peking Univ, Beijing Natl Lab Mol Sci, State Key Lab Struct Chem Unstable & Stable Speci, Coll Chem & Mol Engn, Beijing 100871, Peoples R China..
    Planar FAPbBr(3) Solar Cells with Power Conversion Efficiency above 10%2018In: ACS ENERGY LETTERS, ISSN 2380-8195, Vol. 3, no 8, p. 1808-1814Article in journal (Refereed)
    Abstract [en]

    Bromide-based hybrid perovskites are of particular interest not only due to the fact that they offer a way to go beyond the Shockley-Queisser limit via the tandem cell scheme but single junction devices of them can also achieve reasonably high efficiency with high stability for solar energy conversion. However, the highest power conversion efficiency achieved up to now for FAPbBr(3) single-junction solar cells is only 8.2%, which is far below the efficiency of-17% predicted from detailed balance analysis. Here, a two-step method (the intermolecule exchange pathway) was systematically optimized for the fabrication of high quality FAPbBr(3) films. A molecule of urea, structurally similar to formamidinium, is introduced as an additive to tune the intermolecular ion exchange procedure. SnO2 is introduced as an electron-selective contact to the planar structured FAPbBr(3) solar cells. As a result, a power conversion efficiency of 10.61% and a V-oc of 1.56 V are achieved with planar structured solar cells, both of which represent the highest value ever reported for FAPbBr(3) solar cells.

  • 518.
    Zhao, Ruikai
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Liu, Longcheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Zhao, Li
    Tianjin Univ, Minist Educ China, Key Lab Efficient Utilizat Low & Medium Grade Ene, Tianjin 300350, Peoples R China..
    Deng, Shuai
    Tianjin Univ, Minist Educ China, Key Lab Efficient Utilizat Low & Medium Grade Ene, Tianjin 300350, Peoples R China..
    Li, Shuangjun
    Tianjin Univ, Minist Educ China, Key Lab Efficient Utilizat Low & Medium Grade Ene, Tianjin 300350, Peoples R China..
    Zhang, Yue
    Tianjin Univ, Minist Educ China, Key Lab Efficient Utilizat Low & Medium Grade Ene, Tianjin 300350, Peoples R China..
    Li, Hailong
    Malardalen Univ, Sch Business Soc & Engn, SE-72123 Vasteras, Sweden..
    Techno-economic analysis of carbon capture from a coal-fired power plant integrating solar-assisted pressure-temperature swing adsorption (PTSA)2019In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 214, p. 440-451Article in journal (Refereed)
    Abstract [en]

    This paper presents a techno-economic study to seek the feasibility about the proposed system that integrating solar-assisted pressure-temperature swing adsorption (PTSA) into an 800MWe coal-fired power plant. Solar energy has the potential to supply thermal energy demand for carbon capture, which can avoid the energy consumption of the traditional method such as the steam extraction. The performance of the proposed system is largely affected by the climatic conditions and solar collector's types. The assessment criteria include carbon emission intensity (CEO, levelized cost of electricity (LCOE) and cost of CO2 avoidance (COA). By the parametric analysis, the results show that CEI of the novel system with solar thermal collectors is approximately 2g/kWh lower than that of the referenced power plant with CO2 adsorption capture. In addition, CEI of the novel system can be further decrease with the decline of desorption temperature, adsorption pressure and desorption pressure. For the sake of lower LCOE and COA, the prices of the power plant capacity, adsorbents and solar collectors should be reduced. Specifically, LCOE of the system with evacuated tube collector will be lower than that of the reference system with CO2 capture as the price of solar field is lower than 46.08 USD/m2.

  • 519.
    Zhao, Tao
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Ganji, Suresh
    Schiebe, Christian
    Bohman, Bjorn
    Weinstein, Philip
    Krokene, Paal
    Borg-Karlson, Anna-Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Unelius, C. Rikard
    Convergent evolution of semiochemicals across Kingdoms: bark beetles and their fungal symbionts2019In: The ISME Journal, ISSN 1751-7362, E-ISSN 1751-7370, Vol. 13, no 6, p. 1535-1545Article in journal (Refereed)
    Abstract [en]

    Convergent evolution of semiochemical use in organisms from different Kingdoms is a rarely described phenomenon. Tree-killing bark beetles vector numerous symbiotic blue-stain fungi that help the beetles colonize healthy trees. Here we show for the first time that some of these fungi are able to biosynthesize bicyclic ketals that are pheromones and other semiochemicals of bark beetles. Volatile emissions of five common bark beetle symbionts were investigated by gas chromatography-mass spectrometry. When grown on fresh Norway spruce bark the fungi emitted three well-known bark beetle aggregation pheromones and semiochemicals (exo-brevicomin, endo-brevicomin and trans-conophthorin) and two structurally related semiochemical candidates (exo-1,3-dimethyl-2,9-dioxabicyclo[3.3.1]nonane and endo-1,3-dimethyl-2,9-dioxabicyclo[3.3.1]nonane) that elicited electroantennogram responses in the spruce bark beetle Ips typographus. When grown on malt agar with C-13 D-Glucose, the fungus Grosmannia europhioides incorporated C-13 into exo-brevicomin and trans-conophthorin. The enantiomeric compositions of the fungus-produced ketals closely matched those previously reported from bark beetles. The production of structurally complex bark beetle pheromones by symbiotic fungi indicates cross-kingdom convergent evolution of signal use in this system. This signaling is susceptible to disruption, providing potential new targets for pest control in conifer forests and plantations.

  • 520.
    Zhao, Weijie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Johnson, C. Magnus
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Nano Infrared Microscopy: Obtaining Chemical Information on the Nanoscale in Corrosion Studies2019In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 166, no 11, p. C3456-C3460Article in journal (Refereed)
    Abstract [en]

    In this perspective article, the novel technique "nano infrared microscopy" is introduced as a valuable tool in the field of corrosion science to obtain chemical information with a spatial resolution of around 10 nm. Accordingly, the resolution is well below the diffraction limit, in contrast to conventional vibrational microscopy techniques. Thus, studies of corrosion initiation, localized corrosion, and thin protective films can be performed in greater detail than before. There are a few different types of nano infrared microscopes, but they all have in common that they are based on a combination of infrared (IR) spectroscopy and atomic force microscopy (AFM). In this article the theory of the different techniques is discussed, and some results are highlighted to show the ability of the technique in the field of corrosion science. Future possibilities of the technique in studies of corrosion and degradation of materials are also discussed. 

  • 521.
    Zhao, Yawei
    et al.
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, Inst Energy Sci & Technol,State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Shen, Junyu
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, Inst Energy Sci & Technol,State Key Lab Fine Chem, Dalian 116024, Peoples R China.;Changshu Inst Technol, Sch Chem & Mat Engn, Jiangsu Lab Adv Funct Mat, Changshu 215500, Jiangsu, Peoples R China..
    Yu, Ze
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, Inst Energy Sci & Technol,State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Hu, Maowei
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, Inst Energy Sci & Technol,State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Liu, Chong
    Jinan Univ, Coll Informat Sci & Technol, Inst New Energy Technol, Guangzhou 510632, Guangdong, Peoples R China..
    Fan, Jiandong
    Jinan Univ, Coll Informat Sci & Technol, Inst New Energy Technol, Guangzhou 510632, Guangdong, Peoples R China..
    Han, Hongxian
    Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Catalysis, Dalian Natl Lab Clean Energy, Dalian 116023, Peoples R China..
    Hagfeldt, Anders
    Ecole Polytech Fed Lausanne, Lab Photomol Sci, CH-1015 Lausanne, Switzerland..
    Wang, Mei
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, Inst Energy Sci & Technol,State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, Inst Energy Sci & Technol,State Key Lab Fine Chem, Dalian 116024, Peoples R China.
    Fine-tuning the coordination atoms of copper redox mediators: an effective strategy for boosting the photovoltage of dye-sensitized solar cells2019In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 7, no 20, p. 12808-12814Article in journal (Refereed)
    Abstract [en]

    Natural systems have marvelously utilized copper complexes featuring sulfur-coordinating ligands, known as blue copper proteins, as efficient electron-transfer mediators in biological processes. Copper complexes with sulfur-coordinating ligands have been attempted as redox mediators in dye-sensitized solar cells (DSCs), the performance of which is not yet satisfactory and still remains less well explored. Herein, we report the application of new copper complexes bearing a tetradentate polythioether ligand, [(S-4)Cu](2+/+) (1(2+/+), S-4 = 1,4,8,11-tetrathiocyclotetradecane), as a redox mediator in DSCs in comparison with its N-4-tetradentate counterpart [(N-4)Cu](2+/+) (2(2+/+), N-4 = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane). Impressively, the changes of coordination atoms from N to S positively shift the formal redox potential of the copper complexes by 600 mV, leading to a remarkably high photovoltage approaching 1.0 V. This is one of the highest photovoltage values reported thus far for DSCs based on copper redox mediators.

  • 522.
    Zhou, Nian
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Surface integrity and corrosion behavior of stainless steels after grinding operations2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Stainless steels are widely used in applications where both the mechanical properties of steels and high corrosion resistance are required. There is continuous research to enable stainless steel components to be produced in a more economical way and be used in more harsh environments. A way to achieve this is to correlate the service performance with the production processes.

    The central theme of this thesis is surface integrity and corrosion, especially the stress corrosion cracking behavior, after grinding processes. Controlled grinding parameters, including abrasive grit size, machine power and grinding lubricant, were used and the resulting surface properties studied for austenitic 304L and duplex 2304 stainless steels. The abrasive grit size effect was found to have a larger influence. Surface defects, a highly deformed surface layer and the generation of a high level surface tensile residual stresses along the grinding direction were observed as the main types of damage. 

    The effect of grinding on stress corrosion cracking behavior of austenitic 304L, ferritic 4509 and duplex 2304 stainless steels in chloride-containing environments was also investigated.  The abrasive grit size effect on corrosion behavior for the three grades was compared. Grinding-induced surface tensile residual stress was suggested as the main factor to cause micro-cracks on the ground surface for 304L and 2304; for 4509, grinding-induced grain fragmentation was considered as the main factor for the initiation of extensive micro-pits. For duplex 2304, the microstructure and micro-notches in the as-ground surface also had significant influence. Depending on the surface conditions, the actual loading by four-point bending was found to deviate from the calculated value using the formula according to ASTM G39 by different amounts. The knowledge obtained from this work can provide guidance for choosing appropriate stainless steel grades and grinding parameters; and can also be used to help understanding the failure mechanism of ground stainless steel components during service.

  • 523.
    Zhou, Nian
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Pettersson, Rachel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Schönning, Mikael
    Lin Peng, Ru
    Influence of surface grinding on corrosion behavior of ferritic stainless steels in boiling magnesium chloride solution2018In: Materials and corrosion - Werkstoffe und Korrosion, ISSN 0947-5117, E-ISSN 1521-4176Article in journal (Refereed)
    Abstract [en]

    The influence of grinding operations on surface properties and corrosion behavior of a ferritic stainless steel (FSS), EN 1.4509, has been investigated and limited comparisons also made to the grade EN 1.4622. Surface grinding was performed along the rolling direction of the material. Corrosion tests were conducted in boiling magnesium chloride solution according to ASTM G36; specimens were exposed both without external loading and under four‐point bend loading. The surface topography and cross‐section microstructure before and after exposure were investigated, and residual stresses were measured on selected specimens before and after corrosion tests using X‐ray diffraction. In addition, in situ surface stress measurements were performed to evaluate the actual surface stresses of specimens subject to four‐point bend loading according to ASTM G39. Micro‐pits showing branched morphology initiated from the highly deformed ground surface layer which contained fragmented grains, were observed for all the ground specimens but not those in the as‐delivered condition. Grain boundaries under the surface layer appeared to hinder the corrosion process. No macro‐cracking was found on any specimen after exposure even at high calculated applied loads.

  • 524.
    Zhou, Yuye
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Romson, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Emmer, Åsa
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    An antibody-free sample pretreatment method for osteopontin combined with MALDI-TOF MS/MS analysis2019In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 14, no 3, article id e0213405Article in journal (Refereed)
    Abstract [en]

    Osteopontin is an osteoblast-secreted protein with an aspartic acid-rich, highly phosphorylated, and glycosylated structure. Osteopontin can easily bind to integrins, tumor cells, extracellular matrix and calcium, and is related to bone diseases, various cancers, inflammation etc. Here, DEAE-Cibacron blue 3GA was used to extract recombinant osteopontin from human plasma, and to deplete abundant plasma proteins with an antibody-free method. Using selected buffer systems, osteopontin and human serum albumin could be bound to DEAE-Cibacron blue 3GA, while immunoglobulin G was excluded. The bound osteopontin could then be separated from albumin by using different sequential elution buffers. By this method, 1 μg/mL recombinant osteopontin could be separated from the major part of the most abundant proteins in human plasma. After trypsin digestion, the extracted osteopontin could be successfully detected and identified by MALDI-TOF MS/MS using the m/z 1854.898 peptide and its fragments.

  • 525.
    Zou, Haiyuan
    et al.
    Harbin Inst Technol, Sch Chem & Chem Engn, 92 West Da Zhi St, Harbin 150001, Heilongjiang, Peoples R China.;Southern Univ Sci & Technol, Dept Chem, Shenzhen 518055, Peoples R China.;Southern Univ Sci & Technol, Shenzhen Grubbs Inst, Shenzhen 518055, Peoples R China..
    Li, Ge
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Duan, Lele
    Southern Univ Sci & Technol, Dept Chem, Shenzhen 518055, Peoples R China.;Southern Univ Sci & Technol, Shenzhen Grubbs Inst, Shenzhen 518055, Peoples R China..
    Kou, Zongkui
    Harbin Inst Technol, Sch Chem & Chem Engn, 92 West Da Zhi St, Harbin 150001, Heilongjiang, Peoples R China.;Natl Univ Singapore, Dept Mat Sci & Engn, Singapore 117574, Singapore..
    Wang, John
    Natl Univ Singapore, Dept Mat Sci & Engn, Singapore 117574, Singapore..
    In situ coupled amorphous cobalt nitride with nitrogen-doped graphene aerogel as a trifunctional electrocatalyst towards Zn-air battery deriven full water splitting2019In: Applied Catalysis B: Environmental, ISSN 0926-3373, E-ISSN 1873-3883, Vol. 259, article id UNSP 118100Article in journal (Refereed)
    Abstract [en]

    Herein, we report a new type of efficient trifunctional electrocatalyst by in situ coupling amorphous cobalt nitride (CoNx) nanoparticles within three-dimensional (3D) nitrogen-doped graphene aerogel (NGA). The CoNx/NGA nanohybrid with hierarchical porous strucuture guarantees the superior activities toward ORR, OER and HER, due to abundant dual active CoNx. and NxC sites. Impressively, it also exhibits a long lifetime and exceptionally high electrochemical performances as a cathode and an anode in a two-electrode overall water splitting electrolyzer, and also as an air-cathode in a rechargeable Zn-air battery. In addition, the CoNx/NGA-based water splitting electrolyzer and two Zn-air batteries can be integrated together to effectively self-drive electrochemical water splitting device with high gas evolution rates of 186 and 372 mu mol h(-1) for O-2 and H-2, respectively. This work paves a way for designing advanced non-noble multifunctional catalysts, aiming for the real application of energy storage and conversion devices.

  • 526.
    Örnek, Cem
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Additive manufacturing–a general corrosion perspective2018In: Corrosion Engineering, Science and Technology, ISSN 1478-422X, E-ISSN 1743-2782, Vol. 53, no 7, p. 531-535Article in journal (Refereed)
    Abstract [en]

    Metallic additive manufacturing will replace some materials produced by conventional fabrication methods in the nearest future. However, corrosion will remain an important aspect needed to be prevented. The corrosion behaviour of additively manufactured alloys has been sparsely studied and very little work has been published so far. In this article, a general discussion about materials produced by additive manufacturing will be provided. 

  • 527.
    Örnek, Cem
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. KTH Royal Inst Technol, Sch Engn Sci Chem Biotechnol & Hlth, Div Surface & Corros Sci, Drottning Kristinas Vag 51, S-10044 Stockholm, Sweden..
    Stress Corrosion Cracking and Hydrogen Embrittlement of Type 316L Austenitic Stainless Steel Beneath MgCl2 and MgCl2: FeCl3 Droplets2019In: Corrosion, ISSN 0010-9312, E-ISSN 1938-159X, Vol. 75, no 6, p. 657-667Article in journal (Refereed)
    Abstract [en]

    The atmospheric corrosion, as well as environmentally assisted cracking behavior of 316L austenitic stainless steel (UNS S31603) beneath MgCl2 and MgCl2: FeCl3 droplets under elastic and elastic-plastic strain exposed for 6 months at 50 degrees C and 30% relative humidity were investigated. Shallow and deep corrosion sites with filiform corrosion along with stress corrosion cracking (SCC) were formed beneath the salt-laden droplets, and the potential role of hydrogen embrittlement (HE) and crevice corrosion in damage evolution elucidated. Elastic strain (0.1%) was sufficient to cause SCC cracking as well as HE under droplets with 145 mu g/cmth> of chloride, with the severity of cracking increasing with increasing chloride deposition density (CDD). Elastic-plastic strain (0.2%) increased the propensity to both corrosion and SCC/HE, with cracks seen under droplets having CDD as low as 14.5 mu g/cm(2). Elastic-plastic strain was further seen to facilitate and accelerate pitting corrosion, leading to pits with more penetration depth. The extent of corrosion and cracking increases with increasing chloride deposition density, with ferric ions having more severe effect, in particular promoting localized corrosion with multiple nucleation sites. The work reported here was brought into a larger context of stainless steel corrosion and discussed in light of better understanding atmospheric corrosion of structural components such as nuclear waste storage containers.

  • 528.
    Örnek, Cem
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Engelberg, D. L.
    Univ Manchester, Corros & Protect Ctr, Sackville St, Manchester M13 9PL, Lancs, England.;Univ Manchester, Mat Performance Ctr, Sch Mat, Sackville St, Manchester M13 9PL, Lancs, England..
    Toward Understanding the Effects of Strain and Chloride Deposition Density on Atmospheric Chloride-Induced Stress Corrosion Cracking of Type 304 Austenitic Stainless Steel Under MgCl2 and FeCl3:MgCl2 Droplets2019In: Corrosion, ISSN 0010-9312, E-ISSN 1938-159X, Vol. 75, no 2, p. 167-182Article in journal (Refereed)
    Abstract [en]

    Type 304 (UNS S30400) austenitic stainless steel was exposed for 6 months under elastic (0.1%) and elastic/plastic (0.2%) strain to MgCl2 and mixed MgCl2:FeCl3 droplets with varying chloride deposition densities (1.5 mu g/cm(2)-1,500 mu g/cm(2)) at 30% relative humidity (RH) and 50 degrees C. The occurrence of pitting corrosion, crevice corrosion, atmospheric chloride-induced stress corrosion cracking (AISCC), and hydrogen embrittlement (HE) was observed, and the average crack growth rates estimated. Exposure to elastic/plastic strain resulted in longer and more severe cracks. AISCC was found at chloride deposition densities down to 14.5 mu g/cm(2), whereas no cracks were seen at lower deposition densities, with cracks developing at pit or crevice corrosion sites. More severe cracks were seen under MgCl2 droplets as contrasted to mixed MgCl2:FeCl3 salt droplets, which were seen to promote more localized corrosion sites with deeper penetration and in conjunction with shorter crack lengths. Differences in AISCC propagation rates and associated crack morphologies are discussed in relation to understanding long-term atmospheric corrosion exposures.

  • 529.
    Örnek, Cem
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Leygraf, Christofer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Pan, Jinshan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    On the Volta potential measured by SKPFM - fundamental and practical pects with relevance to corrosion science2019In: Corrosion Engineering, Science and Technology, ISSN 1478-422X, E-ISSN 1743-2782, Vol. 54, no 3, p. 185-198Article, review/survey (Refereed)
    Abstract [en]

    The Volta potential is an electron-sensitive parameter and describes the ermodynamic propensity of a metal to take part in electrochemical actions. It has found widespread acceptance among corrosion searchers due to its connection to the corrosion potential and its sy measurability in local scale, being often used to study localised rrosion phenomena and micro-galvanic activities. The principle object this paper is to provide a comprehensive, fundamental insight into e meaning of the Volta potential and to define a polarity convention measured potentials by the scanning Kelvin probe force microscopy KPFM) in order to assess local nobilities in microstructures. nditions to relate the Volta potential with the mixed-potential theory e discussed and a possible connection to corrosion phenomena plained. The limitations of the Volta potential as well as the SKPFM chnique are also aimed to be explained, with some practical formation to maximise the output of high quality data.

  • 530.
    Örnek, Cem
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Leygraf, Christopher
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Pan, Jinshan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Passive film characterisation of duplex stainless steel using scanning Kelvin probe force microscopy in combination with electrochemical measurements2019In: npJ Materials Degradation, ISSN 2397-2106, Vol. 3, no 1, p. 1-8Article in journal (Refereed)
    Abstract [en]

    The characterisation of passive oxide films on heterogeneous microstructures is needed to assess local degradation (corrosion, cracking) in aggressive environments. The Volta potential is a surface-sensitive parameter which can be used to assess the surface nobility and hence passive films. In this work, it is shown that the Volta potential, measured on super duplex stainless steel by scanning Kelvin probe force microscopy, correlates with the electrochemical properties of the passive film, measured by electrochemical impedance spectroscopy and potentiodynamic polarisation. Natural oxidation by ageing in ambient air as well as artificial oxidation by immersion in concentrated nitric acid improved the nobility, both reflected by increased Volta potentials and electrochemical parameters. Passivation was associated with vanishing of the inherent Volta potential difference between the ferrite and austenite, thereby reducing the galvanic coupling and hence improving the corrosion resistance of the material. Hydrogen-passive film interactions, triggered by cathodic polarisation, however, largely increased the Volta potential difference between the phases, resulting in loss of electrochemical nobility, with the ferrite being more affected than the austenite. A correlative approach of using the Volta potential in conjunction with electrochemical data has been introduced to characterise the nobility of passive films in global and local scale.

  • 531.
    Örnek, Cem
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. Swerea KIMAB AB, Department of Corrosion in Energy and Process Industry.
    Liu, Min
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. University of Science and Technology Beijing, National Center for Materials Service Safety.
    Pan, Jinshan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Jin, Ying
    University of Science and Technology Beijing, National Center for Materials Service Safety.
    Leygraf, Christofer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Volta Potential Evolution of Intermetallics in Aluminum Alloy Microstructure Under Thin Aqueous Adlayers: A combined DFT and Experimental Study2018In: Topics in catalysis, ISSN 1022-5528, E-ISSN 1572-9028, Vol. 61, no 9-11, p. 1169-1182Article in journal (Refereed)
    Abstract [en]

    In this work, first-principle density functional theory (DFT) was used to calculate the work function and Volta potential differences between aluminum alloy matrix and two intermetallic phases (Mg2Si and Al2Cu) with varying surface terminations as a function of adhering monolayers (ML) of water. The calculated data were compared with experimental local Volta potential data obtained by the scanning Kelvin probe force microscopy (SKPFM) on a commercial aluminum alloy AA6063-T5 in atmospheric environments with varying relative humidity (RH). The calculations suggest that the surface termination has a major effect on the magnitude and polarity of the Volta potential of both intermetallic phases (IMP’s). The Volta potential difference between the IMP’s and the aluminum matrix decreases when the surface is gradually covered by water molecules, and may further change as a function of adhering ML’s of water. This can lead to nobility inversions of the IMP’s relative to the aluminum matrix. The measured Volta potential difference between both IMP’s and their neighboring matrix is dependent on RH. Natural oxidation in ambient indoor air for 2 months led to a nobility inversion of the IMP’s with respect to the aluminum matrix, with the intermetallics showing anodic nature already in dry condition. The anodic nature of Al2Cu remained with the introduction of RH, whereas Mg2Si became cathodic at high RH, presumably due to de-alloying of Mg and oxide dissolution. The DFT calculations predicted an anodic character of both IMP’s in reference to the oxidized aluminum matrix, being in good agreement with the SKPFM data. The DFT and SKPFM data were discussed in light of understanding localized corrosion of aluminum alloys under conditions akin to atmospheric exposure.

  • 532.
    Örnek, Cem
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Långberg, Marie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Evertsson, Jonas
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Harlow, Gary
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Linpe, Weronica
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Rullik, Lisa
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Carla, Francesco
    European Synchrotron Radiat Facil, F-38000 Grenoble, France..
    Felici, Roberto
    Area Ric Roma 2 Tor Vergata, SPINCNR, I-00133 Rome, Italy..
    Bettini, Eleonora
    Sandvik Mat Technol, SE-81181 Sandviken, Sweden..
    Kivisakk, Ulf
    Sandvik Mat Technol, SE-81181 Sandviken, Sweden..
    Lundgren, Edvin
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Pan, Jinshan
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    In-situ synchrotron GIXRD study of passive film evolution on duplex stainless steel in corrosive environment2018In: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 141, p. 18-21Article in journal (Refereed)
    Abstract [en]

    This paper presents new findings about the passive film formed on super duplex stainless steel in ambient air and corrosive environments, studied by synchrotron grazing-incidence X-ray diffraction (GIXRD). The passive film, formed in air, was seen to be a nano-crystalline mixed-oxide. Electrochemical polarisation to the passive region in aqueous 1 M NaCl at room temperature resulted in an increase of the passive film thickness, preferential dissolution of Fe, and partial loss of crystallinity. After termination of polarization to the transpassive regime, reformation of the mixed-oxides was observed, showing a thicker, semi-crystalline, and more defective nature (more vacancies) with further new oxides/hydroxides.

  • 533.
    Örnek, Cem
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Långberg, Marie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. Swerim, SE-16407 Kista, Sweden..
    Evertsson, Jonas
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden.;Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Justus Liebig Univ Giessen, Phys Chem Dept, D-35392 Giessen, Germany..
    Harlow, Gary
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Linpe, Weronica
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Rullik, Lisa
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Carla, Francesco
    Diamond Light Source, Didcot OX11 0DE, Oxon, England..
    Felici, Roberto
    SPINCNR, Area Ric Roma 2 Tor Vergata, I-00133 Rome, Italy..
    Kivisakk, Ulf
    Sandvik Mat Technol, SE-81181 Sandviken, Sweden..
    Lundgren, Edvin
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Pan, Jinshan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Influence of Surface Strain on Passive Film Formation of Duplex Stainless Steel and Its Degradation in Corrosive Environment2019In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 166, no 11, p. C3071-C3080Article in journal (Refereed)
    Abstract [en]

    The effect of surface strain on the passive film evolution of SAF 2507 super duplex stainless steel exposed to ambient air and 0.1 M NaCl solution with varying anodic polarization at room temperature has been investigated using in-situ grazing incidence X-ray diffraction (GIXRD) in combination with electrochemical measurements. Surface strain affected the crystallinity of the passive film as such that the surface oxides/hydroxides were predominantly amorphous, with some minor crystalline CrOOH and FeOOH present in the film. Crystalline CrOOH was seen to diminish in volume upon immersion in the NaCl solution, well-possibly becoming amorphous during anodic polarization, whereas crystalline FeOOH was seen to increase in volume during polarization to the passive potential regime. Strain relaxation, associated with metal dissolution, occurred in both austenitic and ferritic grains during immersion in the electrolyte. Anodic polarization to the transpassive regime led to maximum strain relaxation, occurring more on the austenite than the ferrite. The selective transpassive dissolution nature of the ferrite was significantly reduced due to large strains in the austenite. Passive film breakdown was reflected by enhanced dissolution of Fe, Cr, Mo and Ni occurring simultaneously around 1300 mV vs. Ag/AgCl. 

891011 501 - 533 of 533
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