Synthesis and optical and photovoltaic properties of dithienosilole- dithienylpyridine and dithienosilole-pyridine alternate polymers and polymer-B(C6F5)3 complexes

Abstract

Donor-acceptor (D-A)-type alternate polymers were synthesized, with either dithienyldithienosilole or dithienosilole as the donor and pyridine as the acceptor, and they exhibited broad absorption peaks at approximately 520 nm. Complex formation of the polymers with B(C6F5)3 was examined, revealing even broader absorption peaks, with the edges red-shifted relative to the parent polymers. Blend films of the polymers and their complexes with PC71BM were applied as active layers in bulk heterojunction-type polymer solar cells, resulting in a power-conversion efficiency (PCE) of 0.25-1.33%. Treatment of TiO2 electrodes with the polymer solutions led to the attachment of polymer on the TiO2 surface. Using the resulting polymer-attached TiO2 electrodes, dye-sensitized solar cells were fabricated with a PCE of 0.54-0.55%. Copyright © 2013 The Society of Polymer Science, Japan.