Search for dissertations about: "fullerene polymers"

Showing result 11 - 15 of 27 swedish dissertations containing the words fullerene polymers.

  2. 11. Studies of Charge Transport and Energy Level in Solar Cells Based on Polymer/Fullerene Bulk Heterojunction

    Author : Abay Gadisa; Olle Inganäs; Vladimir Dyakonov; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Bulk heterojunction; Charge transport; Space charge limited; Bipolar transport; Origin of open circuit voltage; Polymer-fullerene blend; Soft contact lamination; Polarized infrared emission; Physics; Fysik;

    Abstract : π-Conjugated polymers have attracted considerable attention since they are potential candidates for various opto-electronic devices such as solar cells, light emitting iodes, photodiodes, and transistors. Electronic de vices based on conjugated polymers can be easily processed at low temperature using inexpensive technologies. READ MORE

  4. 12. Morphology studies of thin films of polyfluorene: fullerene blends

    Author : Cecilia Björström; Kjell Magnusson; Mats Fahlman; Karlstads universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik; Physics; Fysik;

    Abstract : The formation of thin films of polymer blends by spin-coating from solution is characterised by rapid solvent quenching, a process that results in non-equilibrium morphologies. Thin films of conjugated polymer blends are used as the active material in polymer solar cells, in which the morphology may have drastic effects on device performance. READ MORE

  5. 13. Surface Energy Patterning and Optoelectronic Devices Based on Conjugated Polymers

    Author : Xiangjun Wang; Olle Inganäs; Henning Sirringhaus; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Surface energy modification; Patterning; Dewetting; Conjugated polymer; plastic solar cell; Low bandgap; Electron acceptors and donors; Physics; Fysik;

    Abstract : 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). READ MORE

  6. 14. Computational Predictions of Conjugated Polymer Properties for Photovoltaic Applications

    Author : Svante Hedström; Beräkningskemi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Conjugated polymers; density functional theory; organic photovoltaics; light-harvesting capabilities; quantum chemistry; absorption spectra; electronic structure; computational predictions;

    Abstract : Organic solar cells employing fullerenes blended with conjugated polymers as the main light-absorbing material have achieved power conversion efficiencies exceeding 10%. They hold promise as an alternative energy source with many advantages in terms of long-term sustainability and reduced greenhouse gas emissions. READ MORE

  7. 15. Excited State Processes in Solar Energy Materials

    Author : Tomas Österman; Kemisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Solar cells; Conjugated polymers; Charge transfer state; Time-resolved spectroscopy; Fluorescence; Artificial Photosynthesis; Bis-tridentate ruthenium II -complexes; Density functional theory; Quantum chemistry.;

    Abstract : This dissertation covers studies of excited state processes in two types of solar energy materials: alternating polyfluorene polymers and their blends with fullerenes in the active layer of plastic solar cells, and bis-tridentate RuII-polypyridyl complexes to be used as sensitizer in systems for artificial photosynthesis. The polymer:fullerene blends were studied by transient absorption and time-resolved fluorescence measurements in order to investigate the role of the charge transfer (CT) state in charge formation. READ MORE