Fabrication and Characterization of Bulk Heterojunction Solar Cells Based on Liquid-Crystal Semiconductive Polymer

Atsushi Suzuki, Shinichi Ogahara, Tsuyoshi Akiyama, Takeo Oku

Department of Materials Science, The University of Shiga Prefecture, Hikone, Japan.

DOI: 10.4236/epe.2012.46060                

Abstract

Bulk heterojunction solar cells based on poly poly(9,9-dioctylfluorene-co-bithiophene) (F8T2) as liquid crystal semiconductive polymer and C₆₀ as electron acceptor were fabricated and characterized. Thermal treatment of the bulk heterojunction films at annealing in the range of glass temperature and liquid crystal transition was performed for tuning optimization with improving the photovoltaic and optical properties. The photovoltaic performance was depended on morphological behavior in active layer at crystal state below glass temperature. The F8T2 thin film worked for electron-donor layer as p-type semiconductor to support charge transfer in active layer. Mechanisms of the photovoltaic properties were discussed on the basis of experimental results.

Keywords

Liquid Crystal Polymer; Bulk Heterojunction Solar Cell; Photovoltaic Property; Optical Property

Conflicts of Interest

The authors declare no conflicts of interest.

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