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  • 551.
    Vandewal, Koen
    et al.
    Hasselt University.
    Tvingstedt, Kristofer
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Manca, Jean V
    Hasselt University.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Charge-Transfer States and Upper Limit of the Open-Circuit Voltage in Polymer: Fullerene Organic Solar Cells2010Ingår i: IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, ISSN 1077-260X, Vol. 16, nr 6, s. 1676-1684Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The power conversion efficiency of polymer: fullerene bulk heterojunction solar cells depends on the generated photocurrent and photovoltage. Here we show, using the thermodynamic theory of detailed balance, that the photovoltage in particular is limited by the presence of polymer: fullerene material interaction, resulting in the formation of a weak donor-acceptor charge transfer complex (CTC). Excited CTCs, or charge transfer (CT) states, are visible in highly sensitive measurements of the absorption and photovoltaic action spectrum, or in photoluminescence and electroluminescence measurements. It is shown that photovoltaic and electroluminescent actions of the polymer: fullerene CTC are related by a reciprocity relation. This relation reproduces the measured open-circuit voltage (V-oc) of the photovoltaic device under solar conditions. Also, the temperature and illumination intensity dependence of V-oc is reproduced by the theory. Assuming perfect conditions for charge generation and recombination, a maximum obtainable V-oc value in function of polymer: fullerene CTC properties is derived.

  • 552.
    Vastesson, Alexander
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Micro-Structuring of New Materials Combined with Electronic Polymers for Interfaces with Cells2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Materials based on novel Off-Stoichiometry Thiol-Ene polymers, abbreviated OSTE, show promising properties as materials forlow cost and scalable manufacturing of micro- and nanosystems such as lab-on-chip devices. The OSTE materials have tunablemechanical properties, offer possibility for low temperature bonding to many surfaces via tunable surface chemistry, and can beused in soft lithography. Unlike the commonly used elastomer poly(dimethylsiloxane), PDMS, the OSTE materials have lowpermeability for gasses, are resistant to common solvents and can be more permanently surface modified.In this master’s thesis project, the OSTE materials have been evaluated with focus on compatibility with cells, possibility fornanostructuring using soft lithography and the use of OSTE as a flexible support for conducting polymers.Results from cell seeding studies with HEP G2 cells suggest that cells can proliferate on a low thiol off-stoichiometry OSTEmaterial for at least five days. The biocompatibility for this type of OSTE material may be similar to poly(styrene). However, highlevels of free thiol monomers in the material decrease cell viability considerably.By using soft lithography techniques it is possible to fabricate OSTE nanochannels with at least the dimensions of 400 nm x 15nm. Combined with the advantages of using the OSTE materials, such as low temperature bonding and possibility for stablesurface modifications, a candidate construction material for future development of systems for DNA analysis is at hand.OSTE can serve as a flexible support for an adsorbed film of a conducting polymer with the possibility for future applicationssuch as electronic interfaces in microsystems. In this project, a film of PEDOT:PSS with the electrical resistance of ~5 kΩ wascreated by adsorption to an flexible OSTE material. Furthermore, results suggest that it is possible to further optimize theconductivity and water resistance of PEDOT:PSS films on OSTE.

  • 553.
    von Kieseritzky, F
    et al.
    Royal Inst Technol, Dept Chem, S-10044 Stockholm, Sweden Linkoping Univ, Dept Phys & Measurement Technol, S-58183 Linkoping, Sweden.
    Hellberg, J
    Royal Inst Technol, Dept Chem, S-10044 Stockholm, Sweden Linkoping Univ, Dept Phys & Measurement Technol, S-58183 Linkoping, Sweden.
    Wang, Xiangjun
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Inganäs, Olle
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Regiospecifically alkylated oligothiophenes via structurally defined building blocks2002Ingår i: Synthesis (Stuttgart), ISSN 0039-7881, E-ISSN 1437-210X, nr 9, s. 1195-1200Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have developed a new synthetic protocol for the unsymmetrically alkylated and halogenated terthiophenes 5 and 10. To demonstrate their usefulness as building blocks for well-defined oligothiophenes, we synthesized a series of seven new sexi-, septi- and octithiophenes. Terthiophene 5 could be dimerized to the didecylsexithiophene In6 and terthiophene 10 to sexithiophene Out6, respectively, by the use of nickel catalysis. Together with the bis-stannylated thiophenes 11 and 12, the septithiophenes In7 and Out7 as well as the octithiophenes In8 and Out8 could be obtained via Stille coupling methodology. We could also obtain the unsymmetrical sexithiophene Unsym6 by selective heterocoupling between one equivalent of terthiophene 5 and 10 each. All new sexi-, septi- and octithiophenes show high photoluminescence in solution, but the quantum yield drops sharply in thin films of the materials.

  • 554.
    Wagner, Michal
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Rebis, Tomasz
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Enhancing charge storage of conjugated polymer electrodes with phenolic acids2016Ingår i: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 302, s. 324-330Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We here present studies of electrochemical doping of poly(1-aminoanthraquinone) (PAAQ) films with three structurally different phenolic acids. The examined phenolic acids (sinapic, ferulic and syringic acid) were selected due to their resemblance to redox active groups, which can be found in lignin. The outstanding electrochemical stability of PAAQ films synthesized for this work enabled extensive cycling of phenolic acid-doped PAAQ films. Potentiodynamic and charge discharge studies revealed that phenolic acid-doped PAAQ films exhibited enhanced capacitance in comparison to undoped PAAQ films, together with appearance of redox activity characteristics specific for each dopant. Electrochemical kinetic studies performed on microelectrodes affirmed the fast electron transfer for hydroquinone-to-quinone reactions with these phenolic compounds. These results imply the potential application of phenolic acids in cheap and degradable energy storage devices. (C) 2015 Elsevier B.V. All rights reserved.

  • 555.
    Wang, Chuan Fei
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Xu, Xiaofeng
    Chalmers, Sweden.
    Zhang, Wei
    Lund University, Sweden.
    Bergqvist, Jonas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Xia, Yuxin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Meng, Xiangyi
    Xi An Jiao Tong University, Peoples R China.
    Bini, Kim
    Chalmers, Sweden.
    Ma, Wei
    Xi An Jiao Tong University, Peoples R China.
    Yartsev, Arkady
    Lund University, Sweden.
    Vandewal, Koen
    Technical University of Dresden, Germany.
    Andersson, Mats R.
    University of South Australia, Australia.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Wang, Ergang
    Chalmers, Sweden.
    Low Band Gap Polymer Solar Cells With Minimal Voltage Losses2016Ingår i: ADVANCED ENERGY MATERIALS, ISSN 1614-6832, Vol. 6, nr 18, artikel-id 1600148Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    One of the factors limiting the performance of organic solar cells (OSCs) is their large energy losses (E-loss) in the conversion from photons to electrons, typically believed to be around 0.6 eV and often higher than those of inorganic solar cells. In this work, a novel low band gap polymer PIDTT-TID with a optical gap of 1.49 eV is synthesized and used as the donor combined with PC 71 BM in solar cells. These solar cells attain a good power conversion efficiency of 6.7% with a high open-circuit voltage of 1.0 V, leading to the E-loss as low as 0.49 eV. A systematic study indicates that the driving force in this donor and acceptor system is sufficient for charge generation with the low E-loss. This work pushes the minimal E-loss of OSCs down to 0.49 eV, approaching the values of some inorganic and hybrid solar cells. It indicates the potential for further enhancement of the performance of OSCs by improving their V-oc since the E-loss can be minimized.

  • 556.
    Wang, Chuanfei
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Ouyang, Liangqi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Xu, Xiaofeng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Braun, Slawomir
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Liu, Xianjie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Relationship of Ionization Potential and Oxidation Potential of Organic Semiconductor Films Used in Photovoltaics2018Ingår i: Solar RRL, ISSN 2367-198X, Vol. 2, nr 9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ultraviolet photoelectron spectroscopy (UPS) and cyclic voltammetry (CV) are employed to measure energy levels for charge transport in organic semiconductor films. A series of classical molecules/polymers used in organic bulk heterojunction solar cells are deposited on platinum substrates/electrodes to form thin films and a linear relationship of vertical ionization potential (IP) measured by UPS and relative oxidation potential (Eox) obtained by CV is found, with a slope equal to unity. The intercept varies with the different reference redox couples and repeated potential sweep numbers during experiment processes. The relationship provides for an easy conversion of values obtained by the two techniques and correlates well with device parameters. The precision in the CV-derived IP values is not sufficient, however, to enable precise design of energy level alignment at heterojunction and the approach does not improve upon the current ?best practice? for obtaining donor ionization potential?acceptor electron affinity gaps at heterojunctions.

  • 557.
    Wang, Chuanfei
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Zhang, Wei
    Division of Chemical Physics, Lund University, Lund, Sweden.
    Meng, Xiangyi
    State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China.
    Bergqvist, Jonas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Liu, Xianjie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Genene, Zewdneh
    Department of Chemistry, Addis Ababa University, Addis Ababa, Ethiopia; Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Göteborg, Sweden.
    Xu, Xiaofeng
    Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Göteborg, Sweden.
    Yartsev, Arkady
    Division of Chemical Physics, Lund University, Lund, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ma, Wei
    State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China.
    Wang, Ergang
    Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Göteborg, Sweden.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Ternary Organic Solar Cells with Minimum Voltage Losses2017Ingår i: Advanced Energy Materials, ISSN 1614-6840, Vol. 7, nr 21, artikel-id 1700390Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new strategy for designing ternary solar cells is reported in this paper. A low-bandgap polymer named PTB7-Th and a high-bandgap polymer named PBDTTS-FTAZ sharing the same bulk ionization potential and interface positive integer charge transfer energy while featuring complementary absorption spectra are selected. They are used to fabricate efficient ternary solar cells, where the hole can be transported freely between the two donor polymers and collected by the electrode as in one broadband low bandgap polymer. Furthermore, the fullerene acceptor is chosen so that the energy of the positive integer charge transfer state of the two donor polymers is equal to the energy of negative integer charge transfer state of the fullerene, enabling enhanced dissociation of all polymer donor and fullerene acceptor excitons and suppressed bimolecular and trap assistant recombination. The two donor polymers feature good miscibility and energy transfer from high-bandgap polymer of PBDTTS-FTAZ to low-bandgap polymer of PTB7-Th, which contribute to enhanced performance of the ternary solar cell.

  • 558.
    Wang, Ergang
    et al.
    Chalmers, Sweden .
    Bergqvist, Jonas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Vandewal, Koen
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ma, Zaifei
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Hou, Lintao
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Lundin, Angelica
    Chalmers, Sweden .
    Himmelberger, Scott
    Stanford University, CA USA .
    Salleo, Alberto
    Stanford University, CA USA .
    Muller, Christian
    Chalmers, Sweden .
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, Mats R.
    Chalmers, Sweden .
    Conformational Disorder Enhances Solubility and Photovoltaic Performance of a Thiophene-Quinoxaline Copolymer2013Ingår i: ADVANCED ENERGY MATERIALS, ISSN 1614-6832, Vol. 3, nr 6, s. 806-814Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The side-chain architecture of alternating copolymers based on thiophene and quinoxaline (TQ) is found to strongly influence the solubility and photovoltaic performance. In particular, TQ polymers with different linear or branched alkyloxy-phenyl side chains on the quinoxaline unit are compared. Attaching the linear alkyloxy side-chain segment at the meta- instead of the para-position of the phenyl ring reduces the planarity of the backbone as well as the ability to order. However, the delocalisation across the backbone is not affected, which permits the design of high-performance TQ polymers that do not aggregate in solution. The use of branched meta-(2-ethylhexyl)oxy-phenyl side-chains results in a TQ polymer with an intermediate degree of order. The reduced tendency for aggregation of TQ polymers with linear meta-alkyloxy-phenyl persists in the solid state. As a result, it is possible to avoid the decrease in charge-transfer state energy that is observed for bulk-heterojunction blends of more ordered TQ polymers and fullerenes. The associated gain in open-circuit voltage of disordered TQ:fullerene solar cells, accompanied by a higher short-circuit current density, leads to a higher power conversion efficiency overall. Thus, in contrast to other donor polymers, for TQ polymers there is no need to compromise between solubility and photovoltaic performance.

  • 559.
    Wang, Ergang
    et al.
    Chalmers.
    Hou, Lintao
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Wang, Zhongqiang
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Hellstrom, Stefan
    Chalmers.
    Mammo, Wendimagegn
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, Mats R
    Chalmers.
    Small Band Gap Polymers Synthesized via a Modified Nitration of 4,7-Dibromo-2,1,3-benzothiadiazole2010Ingår i: ORGANIC LETTERS, ISSN 1523-7060, Vol. 12, nr 20, s. 4470-4473Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The nitration of 4,7-dibromo-2,1,3-benzothiadiazole was modified by using CF3SO3H and HNO3 as the nitrating agent, and the related yield was improved greatly. On the basis of this improvement, two new small band gap polymers, P1TPQ and P3TPQ, were developed. Bulk heterojunction solar cells based on P3TPO and [6,6]-phenyl-C-71-butyric acid methyl ester exhibit interesting results with a power conversion efficiency of 21% and photoresponse up to 1.1 mu m

  • 560.
    Wang, Ergang
    et al.
    Chalmers.
    Hou, Lintao
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Wang, Zhongqiang
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Hellstrom, Stefan
    Chalmers.
    Zhang, Fengling
    Chalmers.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, Mats R
    Chalmers.
    An Easily Synthesized Blue Polymer for High-Performance Polymer Solar Cells2010Ingår i: ADVANCED MATERIALS, ISSN 0935-9648, Vol. 22, nr 46, s. 5240-5244Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    High performance solar cells fabricated from an easily synthesized donor-acceptor polymer show maximum power point up to 6.0 mW cm(-2), with an open-circuit voltage of 0.89 V, short-circuit current density of 10.5 mA cm(-2) and fill factor of 0.64, making this polymer a particularly promising candidate for high-efficiency low-cost polymer solar cells.

  • 561.
    Wang, Ergang
    et al.
    Chalmers.
    Hou, Lintao
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Wang, Zhongqiang
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Ma, Zaifei
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Hellstrom, Stefan
    Chalmers.
    Zhuang, Wenliu
    Chalmers.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, Mats R
    Chalmers.
    Side-Chain Architectures of 2,7-Carbazole and Quinoxaline-Based Polymers for Efficient Polymer Solar Cells2011Ingår i: MACROMOLECULES, ISSN 0024-9297, Vol. 44, nr 7, s. 2067-2073Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Three polymers bearing a common carbazole thiophene quinoxaline thiophene backbone, but different side chains, were designed and synthesized in order to investigate the effect of side chains on their photovoltaic performance. Their photophysical, electrochemical, and photovoltaic properties were investigated and compared. The polymer EWC3, with the largest amount of side chains, showed the highest power conversion efficiency of 3.7% with an open-circuit voltage (V-oc) of 0.92 V. The atomic force microscopy images of the active layers of the devices showed that the morphology was highly influenced by the choice of the solvent and processing additive. It is worth noting that polymer solar cells (PSCs) fabricated from EWC3, with branched side chains on the carbazole units, gave a much higher V-oc than the devices made from EWC1, which bears the same electron-deficient segment as EWC3 but straight side chains on carbazole units. This study offered a useful and important guideline for designing 2,7-carbazole-based polymers for high-performance PSCs.

  • 562.
    Wang, Ergang
    et al.
    Chalmers.
    Ma, Zaifei
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zhang, Zhen
    Chalmers.
    Henriksson, Patrik
    Chalmers.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, Mats R
    Chalmers.
    An isoindigo-based low band gap polymer for efficient polymer solar cells with high photo-voltage2011Ingår i: CHEMICAL COMMUNICATIONS, ISSN 1359-7345, Vol. 47, nr 17, s. 4908-4910Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new low band gap polymer (E-g = 1.6 eV) with alternating thiophene and isoindigo units was synthesized and characterized. A PCE of 3.0% and high open-circuit voltage of 0.89 V were realized in polymer solar cells, which demonstrated the promise of isoindigo as an electron deficient unit in the design of donor-acceptor conjugated polymers for polymer solar cells.

  • 563.
    Wang, Ergang
    et al.
    Chalmers.
    Ma, Zaifei
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zhang, Zhen
    Chalmers.
    Vandewal, Koen
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Henriksson, Patrik
    Chalmers.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, Mats R
    Chalmers.
    An Easily Accessible Isoindigo-Based Polymer for High-Performance Polymer Solar Cells2011Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 133, nr 36, s. 14244-14247Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new, low-band-gap alternating copolymer consisting of terthiophene and isoindigo has been designed and synthesized. Solar cells based on this polymer and PC(71)BM show a power conversion efficiency of 6.3%, which is a record for polymer solar cells based on a polymer with an optical band gap below 1.5 eV. This work demonstrates the great potential of isoindigo moieties as electron-deficient units for building donor-acceptor-type polymers for high-performance polymer solar cells.

  • 564.
    Wang, Heyong
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yu, Hongling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Liu, Xiaoke
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Efficient Light-Emitting Diodes Based on In-Situ Self-Assembled Perovskite Nanocrystals2018Ingår i: ORGANIC LIGHT EMITTING MATERIALS AND DEVICES XXII, SPIE-INT SOC OPTICAL ENGINEERING , 2018, Vol. 10736, artikel-id UNSP 107361FKonferensbidrag (Refereegranskat)
    Abstract [en]

    We introduce a simple and low-cost approach -drop-coating method -for preparation of in-situ self-assembled perovskite nanocrystals for efficient light-emitting diodes. The PL spectrum of the self-assembled NFPI4 nanocrystals thin film prepared by the drop-coating method shows blue shift compared with that of the typical NFPI4 thin film prepared by spin-coating method. In addition, the PL spectra of these self-assembled nanocrystals are tuned from 765 nm to 725 nm by changing usage amounts of the perovskite precursor solution. More importantly, efficient light-emitting diodes with EQEs up to 6.8% are achieved based on these self-assembled NFPI4 nanocrystals.

  • 565.
    Wang, Heyong
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yu, Hongling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Liu, Xiaoke
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Efficient light-emitting diodes based on in-situ self-assembled perovskite nanocrystals2018Ingår i: JOURNAL OF PHOTONICS FOR ENERGY, ISSN 1947-7988, Vol. 8, nr 4, artikel-id 046002Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We introduce a simple and low-cost approach-drop-coating method-for preparation of in-situ self-assembled perovskite nanocrystals for efficient light-emitting diodes (LEDs). The photoluminescence (PL) spectrum of the self-assembled NFPI4 nanocrystals thin film prepared by the drop-coating method shows blue shift compared with that of the typical NFPI4 thin film prepared by the spin-coating method. In addition, the PL spectra of these self-assembled nanocrystals are tuned from 765 to 725 nm by changing usage amounts of the perovskite precursor solution. More importantly, efficient LEDs with external quantum efficiencies up to 6.8% are achieved based on these self-assembled NFPI4 nanocrystals. (C) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)

  • 566.
    Wang, Heyong
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yu, Hongling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Xu, Weidong
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yuan, Zhongcheng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yan, Zhibo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Nanjing Univ, Peoples R China.
    Wang, Chuan Fei
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Liu, Xianjie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Liu, Jun-Ming
    Nanjing Univ, Peoples R China.
    Liu, Xiaoke
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. South China Univ Technol, Peoples R China; Zhejiang Univ, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Efficient perovskite light-emitting diodes based on a solution-processed tin dioxide electron transport layer2018Ingår i: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 6, nr 26, s. 6996-7002Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To achieve high-performance perovskite light-emitting diodes (PeLEDs), an appropriate functional layer beneath the perovskite emissive layer is significantly important to modulate the morphology of the perovskite film and to facilitate charge injection and transport in the device. Herein, for the first time, we report efficient n-i-p structured PeLEDs using solution-processed SnO2 as an electron transport layer. Three-dimensional perovskites, such as CH(NH2)(2)PbI3 and CH3NH3PbI3, are found to be more chemically compatible with SnO2 than with commonly used ZnO. In addition, SnO2 shows good transparency, excellent morphology and suitable energy levels. These properties make SnO2 a promising candidate in both three-and low-dimensional PeLEDs, among which a high external quantum efficiency of 7.9% has been realized. Furthermore, interfacial materials that are widely used to improve the device performances of ZnO-based PeLEDs are also applied on SnO2-based PeLEDs and their effects have been systematically studied. In contrast to ZnO, SnO2 modified by these interfacial materials shows detrimental effects due to photoluminescence quenching.

  • 567.
    Wang, Jianpu
    et al.
    University of Cambridge, England.
    Cheng, Xiaoyang
    University of Cambridge, England.
    Caironi, Mario
    University of Cambridge, England.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Yang, Xudong
    University of Cambridge, England.
    Greenham, Neil C.
    University of Cambridge, England.
    Entirely solution-processed write-once-read-many-times memory devices and their operation mechanism2011Ingår i: Organic electronics, ISSN 1566-1199, E-ISSN 1878-5530, Vol. 12, nr 7, s. 1271-1274Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We investigate the mechanism of operation of low-power write-once-read-many-times (WORM) memory devices based on injection of electrons from ZnO into PEDOT:PSS (polydioxythiophene doped with polystyrenesulfonic acid). Using Raman spectroscopy and in situ absorbance measurements, we directly observe the change of doping level of PEDOT during the device switching. Our results clearly show that the change of device conductance is due to the dedoping of p-doped PEDOT by injected electrons. Based on this understanding, we further demonstrate an entirely solution-processed low-power WORM device by inkjet printing metal electrodes onto arbitrary substrates. (C) 2011 Elsevier B.V. All rights reserved.

  • 568.
    Wang, Jianpu
    et al.
    University of Cambridge, England.
    Chepelianskii, Alexei
    University of Cambridge, England.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Greenham, Neil C.
    University of Cambridge, England.
    Control of exciton spin statistics through spin polarization in organic optoelectronic devices2012Ingår i: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 3, nr 1191Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Spintronics based on organic semiconductor materials is attractive because of its rich fundamental physics and potential for device applications. Manipulating spins is obviously important for spintronics, and is usually achieved by using magnetic electrodes. Here we show a new approach where spin populations can be controlled primarily by energetics rather than kinetics. We find that exciton spin statistics can be substantially controlled by spin-polarizing carriers after injection using high magnetic fields and low temperatures, where the Zeeman energy is comparable with the thermal energy. By using this method, we demonstrate that singlet exciton formation can be suppressed by up to 53% in organic light-emitting diodes, and the dark conductance of organic photovoltaic devices can be increased by up to 45% due to enhanced formation of triplet charge-transfer states, leading to less recombination to the ground state.

  • 569.
    Wang, Jianpu
    et al.
    University of Cambridge, England.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Greenham, Neil C.
    University of Cambridge, England.
    Low-power write-once-read-many-times memory devices2010Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 97, nr 5, artikel-id 053301Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We introduce low-power write-once-read-many-times memory devices fabricated from solution. These devices are based on an electron-only structure using colloidal ZnO semiconductor nanoparticles and the doped conjugated polymer polyethylenedioxythiophene doped with polystyrene sulfonic acid (PEDOT:PSS). The conductive p-doped conjugated polymer is permanently dedoped by injected electrons, producing an insulating state. This demonstration provides a class of memory devices with the potential for extremely low-cost, low-power-consumption applications, such as radio-frequency identification tags. (C) 2010 American Institute of Physics.

  • 570.
    Wang, Jianpu
    et al.
    University of Cambridge, England.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Hallam, Toby
    University of Cambridge, England.
    Greenham, Neil C.
    University of Cambridge, England.
    The surface-state-induced Stark effect in ZnO nanocrystals2010Ingår i: Journal of Physics: Condensed Matter, ISSN 0953-8984, E-ISSN 1361-648X, Vol. 22, nr 39, artikel-id 395009Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Surface states in ZnO nanoparticles play an important role in controlling their electrical transport properties, and these properties can be modified greatly by exposure to UV light. In order to investigate the origin of these effects, we investigate the change in the optical absorption of films of ZnO nanoparticles on exposure to UV light. The modulation spectrum changes from the first derivative to the second derivative of the absorption spectrum as the films are annealed. UV illumination changes the surface states of the nanocrystals, leading to a change in the electric field within the films, which we study using electrostatic force microscopy. The modulation of the optical absorption is found to be consistent with a Stark effect caused by the change in the electric field.

  • 571.
    Wang, Jianpu
    et al.
    University of Cambridge, England.
    Sun, Baoquan
    University of Cambridge, England.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Greenham, Neil C.
    University of Cambridge, England.
    Memristive devices based on solution-processed ZnO nanocrystals2010Ingår i: Physica Status Solidi (a) applications and materials science, ISSN 1862-6300, E-ISSN 1862-6319, Vol. 207, nr 2, s. 484-487Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a memristive device fabricated using low-cost solution-processed colloidal ZnO nanocrystals. Taking advantage of the large surface area of ZnO nanocrystals, we find that an oxygen depletion region can be naturally formed by chemical interaction between an Al electrode and the ZnO nanocrystals. Strong electrical hysteresis, history-dependent conductance, and sweep-rate-dependent current-voltage (J-V) curves are observed in our devices. The resistance can be modified between similar to 1 and similar to 10(4) Omega cm(2), which is promising for application in non-volatile memory devices and in low-cost organic circuits, where typical feature sizes are about 10-100 mu m and the circuit current is low. (C) 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim

  • 572.
    Wang, Jianqiu
    et al.
    Beihang Univ, Peoples R China; Natl Ctr Nanosci and Technol, Peoples R China.
    Xu, Jianqiu
    Nanjing Univ, Peoples R China.
    Yao, Nannan
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zhang, Dongyang
    Beihang Univ, Peoples R China.
    Zheng, Zhong
    Natl Ctr Nanosci and Technol, Peoples R China.
    Xie, Shenkun
    Beihang Univ, Peoples R China; Natl Ctr Nanosci and Technol, Peoples R China.
    Zhang, Xuning
    Beihang Univ, Peoples R China.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zhou, Huiqiong
    Natl Ctr Nanosci and Technol, Peoples R China.
    Zhang, Chunfeng
    Nanjing Univ, Peoples R China.
    Zhang, Yuan
    Beihang Univ, Peoples R China.
    A Comparative Study on Hole Transfer Inversely Correlated with Driving Force in Two Non-Fullerene Organic Solar Cells2019Ingår i: Journal of Physical Chemistry Letters, ISSN 1948-7185, E-ISSN 1948-7185, Vol. 10, nr 14, s. 4110-4116Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report a faster rate of hole transfer under a smaller AHomo in a comparative study of two group organic solar cells (OSCs) consisting of IT-4F as an acceptor and PBDBT and PBDBT-SF as donors. In the OSCs based on PBDBT. SF:IT-4F, a higher short-circuit current (J(SC)) was observed with a Delta(Homo) of 0.31 eV compared to a lower Jsc in PBDBT:IT-4F OSCs with a larger Delta(Homo) (0.45 eV). Intensive investigation indicates that the rate of transfer of a hole from IT-4F to PBDBT-SF or PBDBT is inversely proportional to the Delta(Homo) between IT-4F and donors. The larger Jsc in the PBDBT-SF:IT-4F device is attributed to a synergy of faster hole transfer, slower recombination, and rapid charge extraction enabled by desired morphology and balanced charge carrier mobilities with PBDBT-SF, suggesting that under a sufficiently high Delta(Homo), comprehensive considerations of the transport, film morphology, and energy levels are needed when designing new materials for high-performance OSCs.

  • 573.
    Wang, Lei
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Solin, Niclas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Preparation of functionalized protein materials assisted by mechanochemistry2018Ingår i: Journal of Materials Science, ISSN 0022-2461, E-ISSN 1573-4803, Vol. 53, nr 19, s. 13719-13732Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Herein, we investigate the suitability of hen egg-white lysozyme (HEWL) as a protein matrix for dispersal of various hydrophobic dyes. Moreover, we investigate the use of a mixer mill for grinding operation as an alternative to hand grinding by mortar and pestle. HEWL and various dyes are mixed by mechanochemistry, and the resulting composite material is dissolved in aqueous acid. The samples are then exposed to conditions promoting self-assembly of HEWL into protein nanofibrils (PNFs). The effect of PNF formation on dye photophysics is investigated by spectroscopic examination by absorption and luminescence spectroscopy, and product morphology is examined by scanning electron microscopy. The self-assembly process results in protein nanofibrils functionalized with luminescent dyes. Such structures may find future applications in various devices for light emission. In addition, we demonstrate that the anticancer drug camptothecin can be incorporated into protein nanofibrils giving materials that can find application as drug delivery agents.

  • 574.
    Wang, Ming
    et al.
    Chinese Academy of Science.
    Li, Cuihong
    Beijing Normal University.
    Lv, Aifeng
    Chinese Academy of Science.
    Wang, Zhaohui
    Chinese Academy of Science.
    Bo, Zhishan
    Chinese Academy of Science.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Synthesis and photovoltaic behaviors of benzothiadiazole- and triphenylamine-based alternating copolymers2012Ingår i: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 53, nr 2, s. 324-332Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A series of donor-acceptor (D-A) alternating copolymers (P1, P2 and P3) with thiophene -benzothiadiazole-thiophene-triphenylamine main chain have been synthesized by Suzuki poly-condensation. P1, P2, and P3 possess medium optical band gaps of 1.99, 1.97 and 1.93 eV, respectively. Bulk heterojunction polymer solar cells (BHJ PSCs) with these polymers as donor and PC71BM as acceptor showed power conversion efficiency (PCE) in the range of 2.1-2.8%. The highest PCE of 2.8 % was achieved for P1 with short circuit current (J(SC),) of 7.8 mA/cm(2). This study offers a useful and important insight for designing triphenylamine derivative-based polymers used for efficient PSCs.

  • 575.
    Wang, Nana
    et al.
    Nanjing Technical University of NanjingTech, Peoples R China.
    Cheng, Lu
    Nanjing Technical University of NanjingTech, Peoples R China.
    Ge, Rui
    Nanjing Technical University of NanjingTech, Peoples R China.
    Zhang, Shuting
    Nanjing Technical University of NanjingTech, Peoples R China.
    Miao, Yanfeng
    Nanjing Technical University of NanjingTech, Peoples R China.
    Zou, Wei
    Nanjing Technical University of NanjingTech, Peoples R China.
    Yi, Chang
    Nanjing Technical University of NanjingTech, Peoples R China.
    Sun, Yan
    Nanjing Technical University of NanjingTech, Peoples R China.
    Cao, Yu
    Nanjing Technical University of NanjingTech, Peoples R China.
    Yang, Rong
    Nanjing Technical University of NanjingTech, Peoples R China.
    Wei, Yingqiang
    Nanjing Technical University of NanjingTech, Peoples R China.
    Guo, Qiang
    Nanjing Technical University of NanjingTech, Peoples R China.
    Ke, You
    Nanjing Technical University of NanjingTech, Peoples R China.
    Yu, Maotao
    Nanjing Technical University of NanjingTech, Peoples R China.
    Jin, Yizheng
    Zhejiang University, Peoples R China.
    Liu, Yang
    Zhejiang University, Peoples R China.
    Ding, Qingqing
    Zhejiang University, Peoples R China.
    Di, Dawei
    University of Cambridge, England.
    Yang, Le
    University of Cambridge, England.
    Xing, Guichuan
    Nanjing Technical University of NanjingTech, Peoples R China.
    Tian, He
    Zhejiang University, Peoples R China.
    Jin, Chuanhong
    Zhejiang University, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Friend, Richard H.
    University of Cambridge, England.
    Wang, Jianpu
    Nanjing Technical University of NanjingTech, Peoples R China.
    Huang, Wei
    Nanjing Technical University of NanjingTech, Peoples R China; Nanjing University of Posts and Telecommun, Peoples R China; Nanjing University of Posts and Telecommun, Peoples R China.
    Perovskite light-emitting diodes based on solution-processed self-organized multiple quantum wells2016Ingår i: Nature Photonics, ISSN 1749-4885, E-ISSN 1749-4893, Vol. 10, nr 11, s. 699-+Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Organometal halide perovskites can be processed from solutions at low temperatures to form crystalline direct-bandgap semiconductors with promising optoelectronic properties(1-5). However, the efficiency of their electroluminescence is limited by non-radiative recombination, which is associated with defects and leakage current due to incomplete surface coverage(6-9). Here we demonstrate a solution-processed perovskite light-emitting diode (LED) based on self-organized multiple quantum wells (MQWs) with excellent film morphologies. The MQW-based LED exhibits a very high external quantum efficiency of up to 11.7%, good stability and exceptional highpower performance with an energy conversion efficiency of 5.5% at a current density of 100 mA cm(-2). This outstanding performance arises because the lower bandgap regions that generate electroluminescence are effectively confined by perovskite MQWs with higher energy gaps, resulting in very efficient radiative decay. Surprisingly, there is no evidence that the large interfacial areas between different bandgap regions cause luminescence quenching.

  • 576.
    Wang, Suhao
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Laboratoriet för organisk elektronik. Linköpings universitet, Tekniska fakulteten.
    Fazzi, Daniele
    Univ Cologne, Germany.
    Puttisong, Yuttapoom
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Jafari, Mohammad Javad
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Chen, Zhihua
    Flexterra Corp, IL 60077 USA.
    Ederth, Thomas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Andreasen, Jens W.
    Tech Univ Denmark, Denmark.
    Chen, Weimin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Facchetti, Antonio
    Flexterra Corp, IL 60077 USA; Northwestern Univ, IL 60208 USA; Northwestern Univ, IL 60208 USA.
    Fabiano, Simone
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Effect of Backbone Regiochemistry on Conductivity, Charge Density, and Polaron Structure of n-Doped Donor-Acceptor Polymers2019Ingår i: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 31, nr 9, s. 3395-3406Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We investigated the influence of backbone regiochemistry on the conductivity, charge density, and polaron structure in the widely studied n-doped donor-acceptor polymer poly[N,N-bis(2-octyldodecyl)-1,4,5,8-naphthalenediimide-2,6-diyl]-alt-5,5-(2,2-bithiophene) [P-(NDI2OD-T2)]. In contrast to classic semicrystalline polymers such as poly(3-hexylthiophene) (P3HT), the regioirregular (RI) structure of the naphthalenediimide (NDI)-bithiophene (T2) backbone does not alter the intramolecular steric demand of the chain versus the regioregular (RR) polymer, yielding RI-P(NDI2OD-T2) with similar energetics and optical features as its RR counterpart. By combining the electrical, UV-vis/infrared, X-ray diffraction, and electron paramagnetic resonance data and density functional theory calculations, we quantitatively characterized the conductivity, aggregation, crystallinity, and charge density, and simulated the polaron structures, molecular vibrations, and spin density distribution of RR-/RI-P(NDI2OD-T2). Importantly, we observed that RI-P(NDI2OD-T2) can be doped to a greater extent compared to its RR counterpart. This finding is remarkable and contrasts benchmark P3HT, allowing us to uniquely study the role of regiochemistry on the charge-transport properties of n-doped donor-acceptor polymers.

  • 577.
    Wang, Xiangjun
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Surface Energy Patterning and Optoelectronic Devices Based on Conjugated Polymers2006Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The work presented in this thesis concerns surface energy modification and patterning of the surfaces of conjugated polymers. Goniometry and Wilhelmy Balance techniques were used to evaluate the surface energy or wettability of a polymer’s surface; infrared reflectionabsorption spectroscopy (IRAS) was used to analyse the residuals on the surface as modified by a bare elastomeric stamp poly(dimethylsiloxane) (PDMS). The stamp was found to be capable of modifying a polymer surface. Patterning of a single and/or double layer of conjugated polymers on the surface can be achieved by surface energy controlled dewetting. Modification of a conjugated polymer film can also be carried out when a sample is subjected to electrochemical doping in an aqueous electrolyte. The dynamic surface energy changes during the process were monitored in-situ using the Wilhelmy balance method.

    This thesis also concerns studies of conjugated polymer-based optoelectronics, including light-emitting diodes (PLEDs), that generate light by injecting charge into the active polymer layer, and solar cells (PSCs), that create electrical power by absorbing and then converting solar photons into electron/hole pairs. A phosphorescent metal complex was doped into polythiophene to fabricate PLEDs. The energy transfer from the host polymer to the guest phosphorescent metal (iridium and platinum) complex was studied using photoluminescence and electroluminescence measurements performed at room temperature and at liquid nitrogen temperature. PSCs were prepared using low-bandgap polyfluorene copolymers as an electron donor blended with several fullerene derivatives acting as electron acceptors. Energetic match is the main issue affecting efficient charge transfer at the interface between the polymers and the fullerene derivatives, and therefore the performance of the PSCs. Photoluminescence, luminescence quenching and the lowest unoccupied molecular orbital (LUMO) together with the highest occupied molecular orbital (HOMO) of the active materials in the devices were studied. A newly synthesized fullerene, that could match the low-bandgap polymers, was selected and used as electron acceptor in the PSCs. Photovoltaic properties of these PSCs were characterised, demonstrating one of the most efficient polymer:fullerene SCs that generate photocurrent at 1 μm.

    Delarbeten
    1. PEDOT surface energy pattern controls fluorescent polymer deposition by dewetting
    Öppna denna publikation i ny flik eller fönster >>PEDOT surface energy pattern controls fluorescent polymer deposition by dewetting
    2004 (Engelska)Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 449, nr 1-2, s. 125-132Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    An elastomeric stamp of poly(dimethylsiloxane) (PDMS) can modify the surface energy of some surfaces when brought into conformal contact with these for some time. The substrates under investigation are a conducting polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) and a polyelectrolyte poly(sodium 4-styrenesulfonate) (NaPSS). The changes in surface wetting are characterized by contact angle measurement. Changes are due to the PDMS stamp, which leaves low molecular weight residues on the surface, as shown by infrared reflection absorption spectroscopy. This process may also be operating when other inks are transferred in microcontact printing. Patterning of fluorescent polymer film with feature size of 10–100 μm range is done by confining polymer solutions on the modified surface, by means of spin- or dip-coating. The profile of the patterned film and factors that influence the profile are discussed. This technique is a convenient way to build polymer microstructures for application in organic and biomolecular electronics and photonics.

    Nyckelord
    Surface energy, Surface modification by PDMS stamp, Contact angle analysis, IRA spectrum, Polymer patterning
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-13884 (URN)10.1016/j.tsf.2003.10.153 (DOI)
    Tillgänglig från: 2006-07-07 Skapad: 2006-07-07 Senast uppdaterad: 2018-10-08
    2. Single and bilayer submicron arrays of fluorescent polymer on conducting polymer surface with surface energy controlled dewetting
    Öppna denna publikation i ny flik eller fönster >>Single and bilayer submicron arrays of fluorescent polymer on conducting polymer surface with surface energy controlled dewetting
    2005 (Engelska)Ingår i: Nanotechnology, ISSN 0957-4484, Vol. 16, s. 437-443Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Construction of luminescent single- and bilayer polymer arrays in micron and submicron scales through dewetting on a heterogeneous conducting polymer surface is demonstrated. We study the influence of the pattern geometry and film thickness of polymer dewetting upon annealing, and the morphology of created polymer arrays on the heterogeneous surface. The materials used for patterning are an insulating poly(methyl methacrylate) (PMMA) or a conjugated fluorescent polymer, poly(dioctylphenylthiophene) (PDOPT). The substrate used is the conducting polymer poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT–PSS), with modified heterogeneous surface energy obtained by application of a bare polydimethylsiloxane (PDMS) stamp.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-13885 (URN)10.1088/0957-4484/16/4/018 (DOI)
    Tillgänglig från: 2006-07-07 Skapad: 2006-07-07 Senast uppdaterad: 2018-10-08
    3. In-situ Wilhelmy balance surface energy determination of poly(3-hexylthiophene) and poly(3,4-ethylenedioxythiophene) during electrochemical doping-dedoping
    Öppna denna publikation i ny flik eller fönster >>In-situ Wilhelmy balance surface energy determination of poly(3-hexylthiophene) and poly(3,4-ethylenedioxythiophene) during electrochemical doping-dedoping
    2006 (Engelska)Ingår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 22, nr 22, s. 9287-9294Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Changes in the contact angle between conjugated polymers surface poly(3-hexylthiophene) [P3HT] and poly(3,4-ethylenedioxythiophene) (PEDOT) upon electrochemical doping−dedoping in aqueous electrolyte were determined in situ using a Wilhelmy plate tensiometer in an electrochemical cell. The hydrophobic P3HT was less hydrophobic in the oxidized state than in the neutral state; the more hydrophilic PEDOT was less hydrophilic in the oxidized state than when neutral. The tensiometry results were in good agreement with those measured by contact angle goniometry, and further corroborated by the capillary rise upon doping in a fluid cell with two parallel polymer coated plates, another in situ dynamic determination method. The contact angle changes depend on doping potential, electrolyte type, and concentration. We also deconvoluted the surface energy into components of van der Waals and acid−base interactions, using three probe liquids on the polymer surfaces, ex situ the electrochemical cell. The methods and the obtained results are relevant for the science and technology areas of printed electronics and electrochemical devices and for the understanding of surface energy modification by electrochemical doping.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-13886 (URN)10.1021/la061606p (DOI)
    Tillgänglig från: 2006-07-07 Skapad: 2006-07-07 Senast uppdaterad: 2018-10-08
    4. Electrophosphorescence from substituted poly(thiophene) doped with iridium or platinum complex
    Öppna denna publikation i ny flik eller fönster >>Electrophosphorescence from substituted poly(thiophene) doped with iridium or platinum complex
    2004 (Engelska)Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 468, nr 1-2, s. 226-233Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Electrophosphorescence has been observed in doped polythiophene light-emitting diodes (LEDs) with poly(3-methyl-4-octylthiophene) [PMOT] as host and the phosphorescent compounds bis(2-phenylbenzothiazole) iridium acetylacetonate (BTIr) or platinum(II) 2,8,12,17-tetraethyl-3,7,13,18-tramethyl porphyrin (PtOX) as guest. The photoluminescence (PL) and electroluminescence (EL) of host–phosphorescent guest blends PMOT:BTIr (or PMOT:PtOX) showed the existence of energy transfer from host to guest, which were guest concentration-dependent. At a certain guest concentration, emission from host PMOT was completely quenched in both blends based LEDs, and this gave rise to electrophosphorescence. The PL from host PMOT in the PMOT:BTIr blend film could not be quenched completely but was totally quenched in PMOT:PtOX. This implies a more efficient energy transfer from PMOT to PtOX than that from PMOT to BTIr under optical excitation. Comparison of PL and EL showed that the mechanism of exciton formation at the guest site under electrical excitation was not identical for these two systems. Energy transfer was a dominating route for exciton formation in PMOT:PtOX-based LEDs; charge trapping effect additionally contributed to the formation of exciton at BTIr in PMOT:BTIr-based LEDs. This study demonstrates a new direction in which polythiophene can be a candidate as a host to realize electrophosphorescence in polymer light-emitting diodes (PLEDs). Authors further indicate that to optimize the performance of the polythiophe/phosphorescent complexes, LEDs proper polythiophenes with large bang gap are needed.

    Nyckelord
    Polymer LED, Electrophosphorescence, Energy transfer, Quenching of luminescence, Polythiophene, Phosphorescent complex
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-13887 (URN)10.1016/j.tsf.2004.05.095 (DOI)
    Tillgänglig från: 2006-07-07 Skapad: 2006-07-07 Senast uppdaterad: 2018-10-08
    5. Infrared photocurrent spectral response from plastic solar cell with low-bandgap polyfluorene and fullerene derivative
    Öppna denna publikation i ny flik eller fönster >>Infrared photocurrent spectral response from plastic solar cell with low-bandgap polyfluorene and fullerene derivative
    Visa övriga...
    2004 (Engelska)Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 85, nr 21, s. 5081-5083Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Plastic solar cells were fabricated using a low-band-gap alternating copolymer of fluorene and a donor–acceptor–donor moiety (APFO-Green1), blended with [6,6]-phenyl-C61-butyric acid methylester or 3-(3,5-Bis-trifluoromethylphenyl)-1-(4-nitrophenyl)pyrazolino[60]fullerene as electron acceptors. The polymer shows optical absorption in two wavelength ranges from 300<<500  nm and 650<<1000  nm. Devices based on APFO-Green1 blended with the later fullerene exhibit an outstanding photovoltaic behavior at the infrared range, where the external quantum efficiency is as high as 8.4% at 840  nm and 7% at 900  nm, while the onset of photogeneration is found at 1  µm. A photocurrent density of 1.76  mA/cm2, open-circuit voltage of 0.54  V, and power conversion efficiency of 0.3% are achieved under the illumination of AM1.5 (1000  W/m2) from a solar simulator.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-13888 (URN)10.1063/1.1825070 (DOI)
    Tillgänglig från: 2006-07-07 Skapad: 2006-07-07 Senast uppdaterad: 2018-10-08
    6. Enhanced photocurrent spectral response in low-bandgap polyfluorene and C70-Derivative-Based Solar Cells
    Öppna denna publikation i ny flik eller fönster >>Enhanced photocurrent spectral response in low-bandgap polyfluorene and C70-Derivative-Based Solar Cells
    Visa övriga...
    2005 (Engelska)Ingår i: Advanced Functional Materials, ISSN 1616-301X, Vol. 15, nr 10, s. 1665-1670Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Plastic solar cells have been fabricated using a low-bandgap alternating copolymer of fluorene and a donor-acceptor-donor moiety (APFO-Green1), blended with 3-(3,5-bis-trifluoromethylphenyl)-1-(4-nitrophenyl)pyrazolino[70]fullerene (BTPF70) as electron acceptor. The polymer shows optical absorption in two wavelength ranges, < 500 nm and 600 <  < 1000 nm. The BTPF70 absorbs light at < 700 nm. A broad photocurrent spectral response in the wavelength range 300 <  < 1000 nm is obtained in solar cells. A photocurrent density of 3.4 mA cm-2, open-circuit voltage of 0.58 V, and power-conversion efficiency of 0.7 % are achieved under illumination of AM1.5 (1000 W m-2) from a solar simulator. Synthesis of BTPF70 is presented. Photoluminescence quenching and electrochemical studies are used to discuss photoinduced charge transfer.

    Nyckelord
    Fullerenes, Polyfluorenes, Solar cells - organic
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-13889 (URN)10.1002/adfm.200500114 (DOI)
    Tillgänglig från: 2006-07-07 Skapad: 2006-07-07 Senast uppdaterad: 2018-10-08
    7. Polymer solar cells with low-bandgap polymers blended with C70-derivative give photocurrent at 1 μm
    Öppna denna publikation i ny flik eller fönster >>Polymer solar cells with low-bandgap polymers blended with C70-derivative give photocurrent at 1 μm
    Visa övriga...
    2006 (Engelska)Ingår i: Thin Solid Films, ISSN 0040-6090, Vol. 511-512, s. 576-580Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A new series of low-bandgap alternating polyfluorenes with different donor–acceptor–donor moieties have been synthesized. Electrochemical and optical absorption measurement show that onset bandgaps of these polymers range from 1.2 to 1.5 eV. These polymers, blended with a C70-derivative as acceptor, are used for solar cell fabrication. Devices show promising photovoltaic properties, and the spectral response of photocurrent covers all visible and near-infrared wavelength regions with its onset extended to 1 μm. The best data gives a photocurrent density of 3.4 mA/cm2, open circuit voltage of 0.58 V and power conversion efficiency of 0.7% under illumination of AM1.5 (1000 W/m2) from a solar simulator.

    Nyckelord
    Low-bandgap; Polyfluorene; Fullerene C70-derivative; Solar cell
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-13890 (URN)10.1016/j.tsf.2005.12.013 (DOI)
    Tillgänglig från: 2006-07-07 Skapad: 2006-07-07 Senast uppdaterad: 2018-10-08
  • 578.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, Mats R.
    Department of Organic Chemistry and Polymer Technology, Chalmers University of Technology, Göteborg, Sweden.
    Thomson, Mark E.
    Department of Chemistry, University of Southern California, Los Angeles, USA.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Electrophosphorescence from substituted poly(thiophene) doped with iridium or platinum complex2004Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 468, nr 1-2, s. 226-233Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Electrophosphorescence has been observed in doped polythiophene light-emitting diodes (LEDs) with poly(3-methyl-4-octylthiophene) [PMOT] as host and the phosphorescent compounds bis(2-phenylbenzothiazole) iridium acetylacetonate (BTIr) or platinum(II) 2,8,12,17-tetraethyl-3,7,13,18-tramethyl porphyrin (PtOX) as guest. The photoluminescence (PL) and electroluminescence (EL) of host–phosphorescent guest blends PMOT:BTIr (or PMOT:PtOX) showed the existence of energy transfer from host to guest, which were guest concentration-dependent. At a certain guest concentration, emission from host PMOT was completely quenched in both blends based LEDs, and this gave rise to electrophosphorescence. The PL from host PMOT in the PMOT:BTIr blend film could not be quenched completely but was totally quenched in PMOT:PtOX. This implies a more efficient energy transfer from PMOT to PtOX than that from PMOT to BTIr under optical excitation. Comparison of PL and EL showed that the mechanism of exciton formation at the guest site under electrical excitation was not identical for these two systems. Energy transfer was a dominating route for exciton formation in PMOT:PtOX-based LEDs; charge trapping effect additionally contributed to the formation of exciton at BTIr in PMOT:BTIr-based LEDs. This study demonstrates a new direction in which polythiophene can be a candidate as a host to realize electrophosphorescence in polymer light-emitting diodes (PLEDs). Authors further indicate that to optimize the performance of the polythiophe/phosphorescent complexes, LEDs proper polythiophenes with large bang gap are needed.

  • 579.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Andersson, M.R.
    Department of Organic Chemistry, Chalmers University of Technology, SE-412 96 Göteberg, Sweden.
    Thompson, M.E.
    Department of Chemistry, University Southern California, Los Angeles, CA 90089, United States.
    Inganäs, Olle
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Electrophosphorescence from polythiophene blends light-emitting diodes2003Konferensbidrag (Refereegranskat)
    Abstract [en]

    Electrophosphorescence has been observed in phosphorescent blend polythiophene LEDs with poly(3-methyl-4-octyl-thiophene) (PMOT) as host, bis (2-phenylbenzothiazole) iridium acetylacetonate (BTIr) as the guest. Investigation of photoluminescence and quantum yields shows that energy transfer exists in the host-guest system and depends on guest concentration. Electroluminescence indicates that charge trapping effect also contributes to the formation of exciton at phosphorescent centers.

  • 580.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Berggren, Magnus
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Inganäs, Olle
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Dynamic Control of Surface Energy and Topography of Microstructured Conducting Polymer Films2008Ingår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 24, s. 5942-5948Artikel i tidskrift (Refereegranskat)
    Abstract [en]

     Microstructured polymer surfaces, including conducting and insulating polymers, have been prepared to achieve electrochemical control of the surface energy and topography. The reported surface switches include pillar- and mesh-like surface patterns of polypyrrole (PPy), poly(3,4-ethylene-dioxythiophene) (PEDOT), and photoresists. The structures have been evaluated by contact angle measurements and optical and scanning electron microscopy to determine the surfaces characteristics. These microstructured polymer surface switches can be electrochemically modified from dewetting to wetting conditions, with a maximum associated change of the water contact angle from 129° to 44°. This contact angle switching was observed for samples in which dynamic control of the surface topography and surface tension was coupled. Control of topography was achieved with a dynamic height-switching range of more than 3 ìm. In addition, dynamic control of anisotropic wetting is reported. Our experiments were carried out under conditions that are suitable for a biointerface, implying potential application in biotechnology and cell science. In particular, switching of the energy, chemistry, and topography of the surface, along with their associated orientation, are interesting features for dynamic (electronic) control of the seeding and proliferation for living cells. The technology reported promises for electronically controlled cell-growth within Petri dishes, well plates, and other cell-hosting tools. 

  • 581.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Buyanova, Irina A.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Funktionella elektroniska material. Linköpings universitet, Tekniska högskolan.
    Chen, Weimin
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Funktionella elektroniska material.
    Pan, C.J.
    Department of Electrical and Computer Engineering, University of California, La Jolla, United States, Optical Sciences Center, National Central University, Jhongli, Taoyuan 32001, Taiwan.
    Tu, C.W.
    Department of Electrical and Computer Engineering, University of California, La Jolla, United States.
    Optical characterization studies of grown-in defects in ZnO epilayers grown by molecular beam epitaxy2007Ingår i: Physica. B, Condensed matter, ISSN 0921-4526, E-ISSN 1873-2135, Vol. 401-402, s. 413-416Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Defect formation in ZnO epilayers grown by molecular beam epitaxy (MBE) is studied by employing optical characterization techniques such as photoluminescence (PL) and optically detected magnetic resonance (ODMR). Excess of oxygen during the growth was found to cause an appearance of the PL peak at around 3.338 eV, which indicates that the corresponding defects are predominantly formed in O-rich ZnO. On the other hand, non-stoichiometry during the growth was singled out as the main factor facilitating formation of defects involved in the yellow PL emission band peaking at around 2.17 eV. Several magnetic-resonance active defects are revealed via monitoring this emission and their magnetic-resonance signatures are obtained. © 2007 Elsevier B.V. All rights reserved.

  • 582.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Ederth, Thomas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    In-situ Wilhelmy balance surface energy determination of poly(3-hexylthiophene) and poly(3,4-ethylenedioxythiophene) during electrochemical doping-dedoping2006Ingår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 22, nr 22, s. 9287-9294Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Changes in the contact angle between conjugated polymers surface poly(3-hexylthiophene) [P3HT] and poly(3,4-ethylenedioxythiophene) (PEDOT) upon electrochemical doping−dedoping in aqueous electrolyte were determined in situ using a Wilhelmy plate tensiometer in an electrochemical cell. The hydrophobic P3HT was less hydrophobic in the oxidized state than in the neutral state; the more hydrophilic PEDOT was less hydrophilic in the oxidized state than when neutral. The tensiometry results were in good agreement with those measured by contact angle goniometry, and further corroborated by the capillary rise upon doping in a fluid cell with two parallel polymer coated plates, another in situ dynamic determination method. The contact angle changes depend on doping potential, electrolyte type, and concentration. We also deconvoluted the surface energy into components of van der Waals and acid−base interactions, using three probe liquids on the polymer surfaces, ex situ the electrochemical cell. The methods and the obtained results are relevant for the science and technology areas of printed electronics and electrochemical devices and for the understanding of surface energy modification by electrochemical doping.

  • 583.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Olafsson, S
    Madsen, LD
    Linkoping Univ, Dept Phys, SE-58183 Linkoping, Sweden Swedish Def Res Agcy, FOI, SE-58111 Linkoping, Sweden Royal Inst Technol, Dept Condensed Matter Phys, SE-16440 Stockholm, Sweden.
    Rudner, S
    Ivanov, Ivan Gueorguiev
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Materiefysik.
    Grishin, A
    Linkoping Univ, Dept Phys, SE-58183 Linkoping, Sweden Swedish Def Res Agcy, FOI, SE-58111 Linkoping, Sweden Royal Inst Technol, Dept Condensed Matter Phys, SE-16440 Stockholm, Sweden.
    Helmersson, Ulf
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik.
    Growth and characterization of Na0.5K0.5NbO3 thin films on polycrystalline Pt80Ir20 substrates2002Ingår i: Journal of Materials Research, ISSN 0884-2914, E-ISSN 2044-5326, Vol. 17, nr 5, s. 1183-1191Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Na0.5K0.5NbO3 thin films have been deposited onto textured polycrystalline Pt80Ir20 substrates using radio frequency magnetron sputtering. Films were grown in off- and on-axis positions relative to the target at growth temperatures of 500-700 degreesC and sputtering pressures of 1-7 Pa. The deposited films were found to be textured, displaying a mixture of two orientations (001) and (101). Films grown on-axis showed a prefered (001) orientation, while the off-axis films had a (101) orientation. Scanning electron microscopy showed that the morphology of the films was dependent on the substrate position and sputtering pressure. The low-frequency (10 kHz) dielectric constants of the films were found to be in the range of approximately 490-590. Hydrostatic piezoelectric measurements showed that the films were piezoelectric in the as-deposited form with a constant up to 14.5 pC/N.

  • 584.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Perzon, Erik
    Materials and Surface Chemistry, Chalmers University of Technology, Göteborg, Sweden.
    Delgado, Juan Luis
    Facultad de Ciencias del Medio Ambiente, Universidad de Castilla—La Mancha, Toledo, Spain.
    de la Cruz, Pilar
    Facultad de Ciencias del Medio Ambiente, Universidad de Castilla—La Mancha, Toledo, Spain.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Langa, Fernando
    Facultad de Ciencias del Medio Ambiente, Universidad de Castilla—La Mancha, Toledo, Spain.
    Andersson, Mats
    Materials and Surface Chemistry, Chalmers University of Technology, Göteborg, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Infrared photocurrent spectral response from plastic solar cell with low-bandgap polyfluorene and fullerene derivative2004Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 85, nr 21, s. 5081-5083Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Plastic solar cells were fabricated using a low-band-gap alternating copolymer of fluorene and a donor–acceptor–donor moiety (APFO-Green1), blended with [6,6]-phenyl-C61-butyric acid methylester or 3-(3,5-Bis-trifluoromethylphenyl)-1-(4-nitrophenyl)pyrazolino[60]fullerene as electron acceptors. The polymer shows optical absorption in two wavelength ranges from 300<<500  nm and 650<<1000  nm. Devices based on APFO-Green1 blended with the later fullerene exhibit an outstanding photovoltaic behavior at the infrared range, where the external quantum efficiency is as high as 8.4% at 840  nm and 7% at 900  nm, while the onset of photogeneration is found at 1  µm. A photocurrent density of 1.76  mA/cm2, open-circuit voltage of 0.54  V, and power conversion efficiency of 0.3% are achieved under the illumination of AM1.5 (1000  W/m2) from a solar simulator.

  • 585.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Perzon, Erik
    Mammo, Wendimagegn
    Oswald, Frédéric
    Facultad de Ciencias del Medio Ambiente, Universidad de Castilla-La Mancha, Toledo, Spain.
    Admassie, Shimelis
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Persson, Nils-Krister
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Langa, Fernando
    Facultad de Ciencias del Medio Ambiente, Universidad de Castilla-La Mancha, Toledo, Spain.
    Andersson, Mats R.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Polymer solar cells with low-bandgap polymers blended with C70-derivative give photocurrent at 1 μm2006Ingår i: Thin Solid Films, ISSN 0040-6090, Vol. 511-512, s. 576-580Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new series of low-bandgap alternating polyfluorenes with different donor–acceptor–donor moieties have been synthesized. Electrochemical and optical absorption measurement show that onset bandgaps of these polymers range from 1.2 to 1.5 eV. These polymers, blended with a C70-derivative as acceptor, are used for solar cell fabrication. Devices show promising photovoltaic properties, and the spectral response of photocurrent covers all visible and near-infrared wavelength regions with its onset extended to 1 μm. The best data gives a photocurrent density of 3.4 mA/cm2, open circuit voltage of 0.58 V and power conversion efficiency of 0.7% under illumination of AM1.5 (1000 W/m2) from a solar simulator.

  • 586.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Perzon, Erik
    Materials and Surface Chemistry, Chalmers University of Technology, Göteborg, Sweden.
    Oswald, Frédéric
    Facultad de Ciencias del Medio Ambiente, Universidad de Castilla-La Mancha, Toledo, Spain.
    Langa, Fernando
    Facultad de Ciencias del Medio Ambiente, Universidad de Castilla-La Mancha, Toledo, Spain.
    Admassie, Shimelis
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, Mats R.
    Materials and Surface Chemistry, Chalmers University of Technology, Göteborg, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Enhanced photocurrent spectral response in low-bandgap polyfluorene and C70-Derivative-Based Solar Cells2005Ingår i: Advanced Functional Materials, ISSN 1616-301X, Vol. 15, nr 10, s. 1665-1670Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Plastic solar cells have been fabricated using a low-bandgap alternating copolymer of fluorene and a donor-acceptor-donor moiety (APFO-Green1), blended with 3-(3,5-bis-trifluoromethylphenyl)-1-(4-nitrophenyl)pyrazolino[70]fullerene (BTPF70) as electron acceptor. The polymer shows optical absorption in two wavelength ranges, < 500 nm and 600 <  < 1000 nm. The BTPF70 absorbs light at < 700 nm. A broad photocurrent spectral response in the wavelength range 300 <  < 1000 nm is obtained in solar cells. A photocurrent density of 3.4 mA cm-2, open-circuit voltage of 0.58 V, and power-conversion efficiency of 0.7 % are achieved under illumination of AM1.5 (1000 W m-2) from a solar simulator. Synthesis of BTPF70 is presented. Photoluminescence quenching and electrochemical studies are used to discuss photoinduced charge transfer.

  • 587.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Tvingstedt, Kristofer
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Single and bilayer submicron arrays of fluorescent polymer on conducting polymer surface with surface energy controlled dewetting2005Ingår i: Nanotechnology, ISSN 0957-4484, Vol. 16, s. 437-443Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Construction of luminescent single- and bilayer polymer arrays in micron and submicron scales through dewetting on a heterogeneous conducting polymer surface is demonstrated. We study the influence of the pattern geometry and film thickness of polymer dewetting upon annealing, and the morphology of created polymer arrays on the heterogeneous surface. The materials used for patterning are an insulating poly(methyl methacrylate) (PMMA) or a conjugated fluorescent polymer, poly(dioctylphenylthiophene) (PDOPT). The substrate used is the conducting polymer poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT–PSS), with modified heterogeneous surface energy obtained by application of a bare polydimethylsiloxane (PDMS) stamp.

  • 588.
    Wang, Xiangjun
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Östblom, Mattias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Johansson, Tomas
    Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    PEDOT surface energy pattern controls fluorescent polymer deposition by dewetting2004Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 449, nr 1-2, s. 125-132Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An elastomeric stamp of poly(dimethylsiloxane) (PDMS) can modify the surface energy of some surfaces when brought into conformal contact with these for some time. The substrates under investigation are a conducting polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) and a polyelectrolyte poly(sodium 4-styrenesulfonate) (NaPSS). The changes in surface wetting are characterized by contact angle measurement. Changes are due to the PDMS stamp, which leaves low molecular weight residues on the surface, as shown by infrared reflection absorption spectroscopy. This process may also be operating when other inks are transferred in microcontact printing. Patterning of fluorescent polymer film with feature size of 10–100 μm range is done by confining polymer solutions on the modified surface, by means of spin- or dip-coating. The profile of the patterned film and factors that influence the profile are discussed. This technique is a convenient way to build polymer microstructures for application in organic and biomolecular electronics and photonics.

  • 589.
    Wang, Yaling
    et al.
    Tianjin Key Lab Photoelect Mat and Devices, Peoples R China.
    Liu, Shaowei
    Tianjin Univ Technol, Peoples R China; Tianjin Key Lab Photoelect Mat and Devices, Peoples R China.
    Zeng, Qi
    Tianjin Univ Technol, Peoples R China; Tianjin Key Lab Photoelect Mat and Devices, Peoples R China.
    Wang, Rui
    Tianjin Univ Technol, Peoples R China; Tianjin Key Lab Photoelect Mat and Devices, Peoples R China.
    Qin, Wenjing
    Tianjin Univ Technol, Peoples R China; Tianjin Key Lab Photoelect Mat and Devices, Peoples R China.
    Cao, Huanqi
    Tianjin Univ Technol, Peoples R China; Tianjin Key Lab Photoelect Mat and Devices, Peoples R China.
    Yang, Liying
    Tianjin Univ Technol, Peoples R China; Tianjin Key Lab Photoelect Mat and Devices, Peoples R China.
    Li, Lan
    Tianjin Univ Technol, Peoples R China; Tianjin Key Lab Photoelect Mat and Devices, Peoples R China.
    Yin, Shougen
    Tianjin Univ Technol, Peoples R China; Tianjin Key Lab Photoelect Mat and Devices, Peoples R China.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Enhanced performance and stability of inverted planar perovskite solar cells by incorporating 1,6-diaminohexane dihydrochloride additive2018Ingår i: Solar Energy Materials and Solar Cells, ISSN 0927-0248, E-ISSN 1879-3398, Vol. 188, s. 140-148Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Herein, 1,6-Diaminohexane Dihydrochloride (1,6-DD) is introduced into perovskite precursors to fabricate the inverted planar perovskite solar cells. By regulating the concentration of 1,6-DD additive, the average power conversion efficiency (PCE) of perovskite solar cells is enhanced by 20%. The champion device achieves a relatively high PCE of 17% and an excellent fill factor of 80.1%. The PCE of the large-area (1 cm(2)) device also reaches to 13.68%. After exposure to the air for 16 days, the device with 1,6-DD additive still retains above 90% of the initial efficiency, exhibiting good stability. We demonstrate that a small amount of 1,6-DD affects the crystallization dynamic, yielding ideal perovskite film with enhanced crystallinity and enlarged grain size. The two terminal -NH3+ groups passivates the vacancy defects at the perovskite crystal surface, suppressing charge recombination and facilitating charge transportation effectively. Meanwhile, adjacent crystal surfaces are linked through the hexane alkyl chain of 1,6-DD molecule, which enhances the interaction between perovskite grains and anchors the microstructure of perovskite to some degree. Hydrophobic hexane alkyl chains also increase the moisture resistance of perovskite film. Thus, an easy and effective way is provided for fabricating efficient and stable perovskite solar cells.

  • 590.
    Wang, Yaling
    et al.
    Tianjin University Technology.
    Yang, Liying
    Tianjin University Technology.
    Yao, Cong
    Tianjin University Technology.
    Qin, Wenjing
    Tianjin University Technology.
    Yin, Shougen
    Tianjin University Technology.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Enhanced performance and stability in polymer photovoltaic cells using lithium benzoate as cathode interfacial layer2011Ingår i: SOLAR ENERGY MATERIALS AND SOLAR CELLS, ISSN 0927-0248, Vol. 95, nr 4, s. 1243-1247Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report the enhanced performance and stability of polymer solar cells based on regioregular poly(3-hexylthiophene)(P3HT) and methanofullerene [6,6]-phenyl C-61-butyric acid methyl ester (PCBM) blend using lithium benzoate (C6H5COOLi) as cathode buffer layer between the active layer and the Al cathode. The effects of the C6H5COOLi thickness on the performance of polymer solar cell are also investigated. Under 100 mW/cm(2) white light illumination, the device with 1 nm thick C6H5COOLi as cathode buffer layer exhibits power conversion efficiency (PCE) as high as 3.41 +/- 0.07% and the device stability is greatly extended. Compared to the solar cell with LiF/AI cathode, the PCE is increased ca. 9.4%. Introduction of C6H5COOLi buffer layer effectively increases the shunt resistance and improves the photo-generated charge collection. The improved performance may attribute to the dissociation of semi-conducting C6H5COOLi upon deposition to liberate Li with a low work function, which reduces the interface resistance of the active layer and the cathode and enhances the interior electric field that may result in efficient charge transportion. In addition, the C6H5COOLi layer may serve as an effective oxygen and moisture diffusion barrier for the organic solar cells. Therefore. C6H5COOLi is a promising candidate as an interlayer to improve the efficiency of electron collection and to reduce the ambience influence on the stability of polymer solar cells.

  • 591.
    Wang, Yuming
    et al.
    Nanjing Technical University of NanjingTech, Peoples R China; Nanjing Technical University of NanjingTech, Peoples R China.
    Bai, Sai
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Cheng, Lu
    Nanjing Technical University of NanjingTech, Peoples R China; Nanjing Technical University of NanjingTech, Peoples R China.
    Wang, Nana
    Nanjing Technical University of NanjingTech, Peoples R China; Nanjing Technical University of NanjingTech, Peoples R China.
    Wang, Jianpu
    Nanjing Technical University of NanjingTech, Peoples R China; Nanjing Technical University of NanjingTech, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Huang, Wei
    Nanjing Technical University of NanjingTech, Peoples R China; Nanjing Technical University of NanjingTech, Peoples R China; Nanjing University of Posts and Telecommun, Peoples R China; Nanjing University of Posts and Telecommun, Peoples R China.
    High-Efficiency Flexible Solar Cells Based on Organometal Halide Perovskites2016Ingår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 28, nr 22, s. 4532-4540Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Flexible and light-weight solar cells are important because they not only supply power to wearable and portable devices, but also reduce the transportation and installation cost of solar panels. High-efficiency organometal halide perovskite solar cells can be fabricated by a low-temperature solution process, and hence are promising for flexible-solar-cell applications. Here, the development of perovskite solar cells is briefly discussed, followed by the merits of organometal halide perovskites as promising candidates as high-efficiency, flexible, and light-weight photovoltaic materials. Afterward, recent developments of flexible solar cells based on perovskites are reviewed.

  • 592.
    Wang, Yuming
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Nanjing Tech Univ, Peoples R China.
    Jafari, Mohammad Javad
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Wang, Nana
    Nanjing Tech Univ, Peoples R China.
    Qian, Deping
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ederth, Thomas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Moons, Ellen
    Karlstad Univ, Sweden.
    Wang, Jianpu
    Nanjing Tech Univ, Peoples R China.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Huang, Wei
    Nanjing Tech Univ, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Light-induced degradation of fullerenes in organic solar cells: a case study on TQ1:PC71BM2018Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, nr 25, s. 11884-11889Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The stability of organic solar cells (OSCs) is critical for practical applications of this emerging technology. Unfortunately, in spite of intensive investigations, the degradation mechanisms in OSCs have not been clearly understood yet. In this report, we employ a range of spectroscopic and transport measurements, coupled with drift-diffusion modelling, to investigate the light-induced degradation mechanisms of fullerene-based OSCs. We find that trap states formed in the fullerene phase under illumination play a critical role in the degradation of the open-circuit voltage (V-OC) in OSCs. Our results indicate that the degradation is intrinsic to the fullerenes in OSCs and that alternative acceptor materials are desired for the development of stable OSCs.

  • 593.
    Wang, Yuming
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Qian, Deping
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Cui, Yong
    Chinese Acad Sci, Peoples R China.
    Zhang, Huotian
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Hou, Jianhui
    Chinese Acad Sci, Peoples R China.
    Vandewal, Koen
    Hasselt Univ, Belgium.
    Kirchartz, Thomas
    Forschungszentrum Julich, Germany; Univ Duisburg Essen, Germany; Univ Duisburg Essen, Germany.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Optical Gaps of Organic Solar Cells as a Reference for Comparing Voltage Losses2018Ingår i: ADVANCED ENERGY MATERIALS, ISSN 1614-6832, Vol. 8, nr 28, artikel-id 1801352Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The voltage loss, determined by the difference between the optical gap (E-g) and the open-circuit voltage (V-OC), is one of the most important parameters determining the performance of organic solar cells (OSCs). However, the variety of different methods used to determine E-g makes it hard to fairly compare voltages losses among different material systems. In this paper, the authors discuss and compare various E-g determination methods and show how they affect the detailed calculation of voltage losses, as well as predictions of the maximum achievable power conversion efficiency. The aim of this paper is to make it possible for the OSC community to compare voltage losses in a consistent and reasonable way. It is found that the voltage losses for strongly absorbed photons in state-of-the-art OSCs are not much less than 0.6 V, which still must be decreased to further enhance efficiency.

  • 594.
    Wang, Z. Q.
    et al.
    Nanjing University, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Wang, K. F.
    Nanjing University, Peoples R China.
    Yu, H.
    Nanjing University, Peoples R China.
    Ren, Z. F.
    Nanjing University, Peoples R China.
    Liu, J. -M.
    Nanjing University, Peoples R China.
    Synthesis and magnetic properties of Pr0.57Ca0.43MnO3 nanoparticles2007Ingår i: Materials Science & Engineering: B. Solid-state Materials for Advanced Technology, ISSN 0921-5107, E-ISSN 1873-4944, Vol. 136, nr 1, s. 96-100Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pr0.57Ca0.43MnO3 nanoparticles with an average particle size of similar to 20 nm have been synthesized using hydrothermal method in combination with post-annealing, and characterized using X-ray diffraction, X-ray photoelectron spectrometer, high-resolution transmission electron microscopy and superconducting quantum interference device magnetometery. The results show that the hydrothermal synthesis of Pr1-xCaxMnO3 compound below 240 degrees C is difficult. The Pr0.57Ca0.43MnO3 nanoparticles obtained by annealing the hydrothermal products at 900 degrees C for 2 h present an orthorhombic perovskite structure with the same lattice as bulk Pr0.6Sr0.4MnO3. Magnetic characterization reveals that the low-temperature antiferromagnetic and charge ordering transitions identified in bulk Pr0.57Ca0.43MnO3 are completely suppressed in the nanoparticles, while a ferromagnetic transition occurs at -110 K. The spin-freezing behavior at low temperature for the Pr0.57Ca0.43MnO3 nanoparticles is demonstrated. (c) 2006 Elsevier B.V. All rights reserved.

  • 595.
    Wang, Zhongqiang
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Wang, E.
    Chalmers University of Technology, Göteborg, Sweden.
    Hou, Lintao
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, M.
    Chalmers University of Technology, Göteborg, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Mixed solvents for reproducible photovoltaic bulk heterojunctions2011Ingår i: Journal of Photonics for Energy, ISSN 1947-7988, Vol. 1, nr 1Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Most efficient polymer solar cells are usually fabricated from toxic organic solvents, such as chloroform, chlorobenzene, or dichlorobenzene (ODCB). Here, we demonstrate a power conversion efficiency of 4.5% in solar cells with a new blue polymer poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt- thiophene-2,5-diyl] (TQ1) mixed with PC71BM and processed from mixed solvents of toluene and ODCB in a ratio of 9:1. Decreasing the content of ODCB makes device processing more compatible with the environment for large scale production, with 10% reduction of photocurrent compared to devices from pure ODCB under optimized conditions. In addition, less variation of photocurrent is obtained in solar cells processed from mixed solvents than from pure ODCB due to varying nanostructure in the blends, which is also critical for production. © 2011 Society of Photo-Optical Instrumentation Engineers (SPIE).

  • 596.
    Wigenius, Jens
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Conjugated Polyelectrolytes in Interactions with Biomolecules for Supramolecular assembly and Sensing2010Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Conjugated polyelectrolytes (CP) show interesting electrical and optical properties for organic electronics as well as for life science applications. Their possibilities of supramolecular assembly with nanowire like misfolded proteins, amyloids, as well as synthetic polypeptides or DNA forming conducting or luminescent nano composites is highly interesting as being a truly bottom up approach for fabrication of OLEDs, photovoltaic’s as well as logic devices. The conformation and aggregation dependent luminescence properties from the special class of CPs, Luminescent conjugated polyelectrolytes (LCP), have been utilised and developed as sensors to follow and study biomolecular interactions, DNA hybridisation, protein-protein interactions and staining of living cell cultures and tissue slides. In this thesis we are bringing the evolution a few steps further by applying new types of experimental techniques, such as light scattering and fluorescence correlation spectroscopy, combined with standard techniques as soft lithography and different spectroscopy techniques, to gain better knowledge of the optical behaviour of LCPs and their interactions with biomolecules. We explore the optical properties and vibronic transitions of LCPs; their ability of resonance energy transfer with LCPs indicating super lightning behaviour; the opposite fluorescence shift when interacting with α-helical rich polypeptides compared to earlier reports of interactions upon staining of β-rich amyloids; and the possibility of LCPs to influence protein aggregation as well as the possibility of fabricating biochips based on LCPs and soft lithography. Here we also show fundamental limitations to patterning using macromolecular fluids, of general relevance to soft lithography and nanoimprint lithography with low viscosity polymers.

    Delarbeten
    1. Limits to Nanopatterning of Fluids on Surfaces in Soft Lithography
    Öppna denna publikation i ny flik eller fönster >>Limits to Nanopatterning of Fluids on Surfaces in Soft Lithography
    2008 (Engelska)Ingår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 18, nr 17, s. 2563-2571Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Soft lithographic microcontact printing using the residual polydimethylsiloxane (PDMS) found in elastomeric PDMS stamps is demonstrated to lead to unstable prints with sub-micrometer dimensions. The statics and dynamics of the process have been followed with time-resolved atomic force microscopy, imaging ellipsometry, water contact angle measurement, and optical diffraction. It is proposed that this instability places a fundamental limitation on patterning by macromolecular fluids, which is of general relevance to soft lithography and nanoimprint lithography with low viscosity polymers.

    Nyckelord
    Lithography, microcontact printing (µCP), nanostructures, nanowires, surface patterning
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-42810 (URN)10.1002/adfm.200800073 (DOI)68960 (Lokalt ID)68960 (Arkivnummer)68960 (OAI)
    Tillgänglig från: 2009-10-10 Skapad: 2009-10-10 Senast uppdaterad: 2017-12-13
    2. Protein biochips patterned by microcontact printing or by adsorption-soft lithography in two modes
    Öppna denna publikation i ny flik eller fönster >>Protein biochips patterned by microcontact printing or by adsorption-soft lithography in two modes
    2008 (Engelska)Ingår i: BIOINTERPHASES, ISSN 1559-4106 , Vol. 3, nr 3, s. 75-82Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Patterning of proteins is critical to protein biochips. Printing of layers of proteins is well established, as is adsorption of proteins to surfaces properly modified with surface chemical functionalities. The authors show that simple methods based on soft lithography stamps can be used to prepare functional antibody chips through both these routes. Both methods incorporate transfer of the stamp material poly (dimethylsiloxane) (PDMS) to the biochip, whether intended or not intended. The results indicate that microcontact printing of proteins always includes PDMS transfer, thereby creating a possibility of unspecific adsorption to a hydrophobic domain.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-17907 (URN)10.1116/1.2988771 (DOI)
    Tillgänglig från: 2009-04-26 Skapad: 2009-04-24 Senast uppdaterad: 2010-04-20
    3. DNA Chips with Conjugated Polyelectrolytes in Resonance Energy Transfer Mode
    Öppna denna publikation i ny flik eller fönster >>DNA Chips with Conjugated Polyelectrolytes in Resonance Energy Transfer Mode
    Visa övriga...
    2010 (Engelska)Ingår i: LANGMUIR, ISSN 0743-7463, Vol. 26, nr 5, s. 3753-3759Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    We show how to use well-defined conjugated polyelectrolytes (CPEs) combined With Surface energy patterning to Fabricate DNA Chips utilizing A fluorescence signal amplification. Cholesterol-modified DNA strands in complex with it CPE are adsorbed to a surface energy pattern, formed by printing with soft elastomer stamps. Hybridization of the surface bound DNA strands with it short complementary strand from Solution is monitored using both fluorescence microscopy and imaging surface plasmon resonance. The CPEs act as antennas, enhancing resonance energy transfer to the dye-labeled DNA when complementary hybridization of the double strand occurs.

    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-54255 (URN)10.1021/la903101v (DOI)000274636900113 ()
    Tillgänglig från: 2010-03-05 Skapad: 2010-03-05 Senast uppdaterad: 2015-05-29
    4. Oligothiophene Assemblies Defined by DNA Interaction: From Single Chains to Disordered Clusters
    Öppna denna publikation i ny flik eller fönster >>Oligothiophene Assemblies Defined by DNA Interaction: From Single Chains to Disordered Clusters
    Visa övriga...
    2009 (Engelska)Ingår i: SMALL, ISSN 1613-6810 , Vol. 5, nr 1, s. 96-103Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The organization of conjugated polyelectrolytes (CPEs) interacting with biomolecules sets conditions for the biodetection of biological processes and identity, through the use of optical emission from the CPE. Herein, a well-defined CPE and its binding to DNA is studied. By using dynamic light scattering and circular dichroism spectroscopy, it is shown that the CPE forms a multimolecule ensemble in aqueous solution that is more than doubled it? size when interacting with a small DNA chain, while single chains are evident in ethanol. The related changes in the fluorescence spectra upon polymer aggregation are assigned to oscillator strength redistribution between vibronic transitions in weakly coupled H-aggregates. An enhanced single-molecule spectroscopy technique that allows full control of excitation and emission light polarization is applied to combed and decorated;,DNA chains. It is found that the organization of combed CPE-lambda DNA complexes (when dry on the surface) allows considerable variation of CPE distances and direction relative to the DNA chain. By analysis of the polarization data. energy transfer between the polymer chains in individual complexes is confirmed and their sizes estimated.

    Nyckelord
    aggregation, conjugated polymers, DNA, fluorescence, single-molecule spectroscopy
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-16829 (URN)10.1002/smll.200800855 (DOI)
    Tillgänglig från: 2009-02-20 Skapad: 2009-02-20 Senast uppdaterad: 2010-04-20
    5. Dark states in oligothiophenes: evidence from fluorescence correlation spectroscopy and dynamic light scattering
    Öppna denna publikation i ny flik eller fönster >>Dark states in oligothiophenes: evidence from fluorescence correlation spectroscopy and dynamic light scattering
    Visa övriga...
    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    We report studies of the conjugated pentameric oligothiophene derivative p-FTAA, which changes optical properties in aqueous buffers of varying pH and concentration. Using dynamic light scattering, luminescence spectroscopy and fluorescence correlation spectroscopy, we find evidence for the formation of large clusters of p-FTAA in aqueous environment, formation of very large non-emissive clusters, and the presence of at least two dark transient states, one presumably being a triplet state. The clustering of p-FTAA is therefore an important mechanism. This work provides an interpretation of fluorescence spectra used for the detection of misfolding proteins through interaction with p-FTAA.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-54897 (URN)
    Tillgänglig från: 2010-04-20 Skapad: 2010-04-20 Senast uppdaterad: 2014-04-08
    6. Interactions between a luminescent conjugated oligoelectrolyte and insulin during early phases of amyloid formation
    Öppna denna publikation i ny flik eller fönster >>Interactions between a luminescent conjugated oligoelectrolyte and insulin during early phases of amyloid formation
    2011 (Engelska)Ingår i: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 11, nr 8, s. 1120-1127Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Folding of an amino acid polypeptide chain into its native three-dimensional protein is a delicate process. Misfolding may cause assembly of dysfunctional proteins leading to aggregated assemblies, in medicine denoted amyloids, causing Alzheimer’s, Parkinson and a number of other protein related diseases. Amyloids have also shown promising results as building blocks in organic electronic applications, associated to conjugated polymers. Luminescent conjugated oligo- and polythiophenes (LCPs) have been further developed for biosensor applications exhibiting good ability to discriminate and determine different types of amyloid enrichment in complex environments, such as in tissue sections. The nature of interaction between the amyloid assemblies and LCPs is still not fully understood. In this study we use steady-state fluorescence spectroscopy, dynamic light scattering, transmission electron microscopy and fluorescence correlation spectroscopy to follow the interplay between the anionic oligothiophene derivative 4',3'''-Bis-carboxymethyl-[2,2';5',2'';5'',2''';5''',2'''']quinque thiophene-5,5''''-dicarboxylic acid (p-FTAA), and prefibrillar protein assemblies present during the earlier stage of in vitro fibrillation of bovine insulin. Our findings confirm that p-FTAA interacts with pre-fibrillar species of insulin preceding the formation of mature insulin amyloid fibrils, and insights regarding the molecular interplay between p-FTAA and these species are provided.

    Ort, förlag, år, upplaga, sidor
    Wiley, 2011
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-54898 (URN)10.1002/mabi.201100016 (DOI)000294160900011 ()
    Anmärkning
    Funding Agencies|Swedish Science Council (VR)||Strategic Research Foundation (SSF) through the center for organic bioelectronics (OBOE)||Knut and Alice Wallenberg foundation||Tillgänglig från: 2010-04-20 Skapad: 2010-04-20 Senast uppdaterad: 2017-12-12
    7. Supramolecular Assembly of Designed α-Helical Polypeptide-Based Nanostructures and Luminescent Conjugated Polyelectrolytes
    Öppna denna publikation i ny flik eller fönster >>Supramolecular Assembly of Designed α-Helical Polypeptide-Based Nanostructures and Luminescent Conjugated Polyelectrolytes
    2010 (Engelska)Ingår i: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 10, nr 8, s. 836-841Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Designed polypeptides with controllable folding properties are utilized as supramolecular templates for fabrication of ordered nanoscale molecular and fibrous assemblies of luminescent conjugated polymers (LCPs). The properties of the LCPs as well as the three dimensional conformation of the polypeptide-scaffold determine how the polymers are arranged in the supramolecular construct, which highly affects the properties of the hybrid material. The ability to control the polypeptide conformation and assembly into fibers provide a promising route for tuning the optical properties of LCPs and for fabrication of complex functional supramolecules with well defined structural properties.

    Ort, förlag, år, upplaga, sidor
    John Wiley & Sons, 2010
    Nyckelord
    α-helical; conjugated polymers; hybrid materials; peptides; self-assembly
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-54899 (URN)10.1002/mabi.200900463 (DOI)000281387900002 ()
    Tillgänglig från: 2010-04-20 Skapad: 2010-04-20 Senast uppdaterad: 2017-12-12Bibliografiskt granskad
    8. Synthetic Polypeptides as Scaffolds for Supramolecular Assembly of Conducting Polymer Nanocomposites
    Öppna denna publikation i ny flik eller fönster >>Synthetic Polypeptides as Scaffolds for Supramolecular Assembly of Conducting Polymer Nanocomposites
    Visa övriga...
    2010 (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    The development of nanoelectronics has resulted in enormous advancements in fabrication techniques that have enabled massproduction of CMOS circuits with feature sizes below 45nm. There is a large interest in new methods to further push the size limits, lower the production costs and to facilitate the design of more advanced three-dimensional structures beyond today’s 2.5 dimensional architectures. Self-assembly is probably the most important scheme in this development and is currently applied to many different areas and classes of nanoelectronics. Self-assembly enables fabrication of structures well below 10 nm in feature size and allows for incorporation of novel nanomaterials, such as metallic and semiconducting nanoparticles with many interesting optical and electrical properties. The controlled self-assembly of electro-active nanocomposites is of great interest for the development of novel functional materials including biosensors, electrochromic/plasmonic hybrid devices, and polymer/nanoparticle-based memories.

    Nyckelord
    Conducting Polymers, Organic Electronics, Conducting Nanowires, Self- Assembly, Supramolecular Materials
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-54901 (URN)
    Tillgänglig från: 2010-04-20 Skapad: 2010-04-20 Senast uppdaterad: 2010-04-20
  • 597.
    Wigenius, Jens A.
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Persson, Gustav
    Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
    Nilsson, Peter
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Organisk Kemi. Linköpings universitet, Tekniska högskolan.
    Widengren, Jerker
    Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Dark states in oligothiophenes: evidence from fluorescence correlation spectroscopy and dynamic light scatteringManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    We report studies of the conjugated pentameric oligothiophene derivative p-FTAA, which changes optical properties in aqueous buffers of varying pH and concentration. Using dynamic light scattering, luminescence spectroscopy and fluorescence correlation spectroscopy, we find evidence for the formation of large clusters of p-FTAA in aqueous environment, formation of very large non-emissive clusters, and the presence of at least two dark transient states, one presumably being a triplet state. The clustering of p-FTAA is therefore an important mechanism. This work provides an interpretation of fluorescence spectra used for the detection of misfolding proteins through interaction with p-FTAA.

  • 598.
    Wigenius, Jens A.
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Persson, Gustav
    Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
    Widengren, Jerker
    Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Interactions between a luminescent conjugated oligoelectrolyte and insulin during early phases of amyloid formation2011Ingår i: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 11, nr 8, s. 1120-1127Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Folding of an amino acid polypeptide chain into its native three-dimensional protein is a delicate process. Misfolding may cause assembly of dysfunctional proteins leading to aggregated assemblies, in medicine denoted amyloids, causing Alzheimer’s, Parkinson and a number of other protein related diseases. Amyloids have also shown promising results as building blocks in organic electronic applications, associated to conjugated polymers. Luminescent conjugated oligo- and polythiophenes (LCPs) have been further developed for biosensor applications exhibiting good ability to discriminate and determine different types of amyloid enrichment in complex environments, such as in tissue sections. The nature of interaction between the amyloid assemblies and LCPs is still not fully understood. In this study we use steady-state fluorescence spectroscopy, dynamic light scattering, transmission electron microscopy and fluorescence correlation spectroscopy to follow the interplay between the anionic oligothiophene derivative 4',3'''-Bis-carboxymethyl-[2,2';5',2'';5'',2''';5''',2'''']quinque thiophene-5,5''''-dicarboxylic acid (p-FTAA), and prefibrillar protein assemblies present during the earlier stage of in vitro fibrillation of bovine insulin. Our findings confirm that p-FTAA interacts with pre-fibrillar species of insulin preceding the formation of mature insulin amyloid fibrils, and insights regarding the molecular interplay between p-FTAA and these species are provided.

  • 599.
    Wigenius, Jens
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Björk, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Hamedi, Mahiar
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Aili, Daniel
    Department of Materials, Imperial College London, SW7 2AZ London, UK.
    Supramolecular Assembly of Designed α-Helical Polypeptide-Based Nanostructures and Luminescent Conjugated Polyelectrolytes2010Ingår i: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 10, nr 8, s. 836-841Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Designed polypeptides with controllable folding properties are utilized as supramolecular templates for fabrication of ordered nanoscale molecular and fibrous assemblies of luminescent conjugated polymers (LCPs). The properties of the LCPs as well as the three dimensional conformation of the polypeptide-scaffold determine how the polymers are arranged in the supramolecular construct, which highly affects the properties of the hybrid material. The ability to control the polypeptide conformation and assembly into fibers provide a promising route for tuning the optical properties of LCPs and for fabrication of complex functional supramolecules with well defined structural properties.

  • 600.
    Wigenius, Jens
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Fransson, Sophia
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Inganäs, Olle
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Conjugated Polyelectrolytes as Reporter Molecules2007Ingår i: E-MRS 2007 Strasbourg,2007, 2007Konferensbidrag (Refereegranskat)
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