Synthesis of new conjugated donor-acceptor type polymers for photovoltaic device applications

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2015
Akpınar, Hava Zekiye
Electrochromism and photoelectric effect are the mostly investigated areas of conducting polymers. In electrochromism, electrochemical parameters of the polymers are firstly examined. Spectroelectrochemical studies are performed with specified wavelengths. Parameters, such as optical contrast and switching times of the polymer films are explored. In bulk heterojunction polymer solar cells, semiconducting polymer materials in combination with fullerene are used as the active layer. Photons are absorbed by conjugated polymer and strongly bounded excitons are formed. In order to efficiently separate the bounded electron hole pairs, HOMO and LUMO levels of the polymer and fullerene should be compatible with each other. The performance of the devices is also highly dependent on the molecular structure of the polymer side chains. In this thesis study, five novel conjugated polymers containing donor-acceptor units such as thiazolothiazole, thiophene, furan, benzotriazole and fluorene were synthesized via Suzuki and Stille coupling polymerizations. Electrochemical and optical properties of the polymers were examined and bulk heterojunction organic photovoltaic devices were fabricated using (C 61) fullerene. Solar cell parameters such as open circuit voltage, short circuit current density, fill factor and power conversion efficiency were measured.

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Citation Formats
H. Z. Akpınar, “Synthesis of new conjugated donor-acceptor type polymers for photovoltaic device applications,” Ph.D. - Doctoral Program, Middle East Technical University, 2015.