Polythiophenoazomethines – alternate photoactive materials for organic photovoltaics

Abstract

Solution-processable polyazomethines containing thiophenes were synthesized and used as the donor material in bulk heterojunction solar cells. The blue polymers exhibited similar electrochemical properties to the benchmark P3HT with the advantage of absorbing more of the visible spectrum. The resulting photovoltaic devices using polyazomethines in the photoactive layer with PC₆₀BM as the acceptor showed power conversion efficiencies up to 0.22% under simulated 100 mW cm⁻² AM 1.5G irradiation. The low efficiencies are ascribed to poor charge generation because of too coarse bulk heterojunction morphology formation.