Acceptor Properties of Boron Subphthalocyanines in Fullerene Free Photovoltaics

Abstract

In this paper, we discuss the use of the typical electron-donor (donor) material boron subphthalocyanine chloride (Cl-BsubPc) and a chlorinated derivative (hexachloro boron subphthalocyanine chloride, Cl–Cl6BsubPc) to act as electron-accepting (acceptor) materials and as replacements for C60, when coupled with tetracene and pentacene as the electron-donor materials in organic photovoltaics (OPVs). A large decrease in photocurrent was observed when C60 was replaced in the pentacene OPVs, although there was evidence of the harvesting of some triplets for the pentacene/Cl–Cl6BsubPc OPV. Large increases in Voc and stability were observed. Photoluminescence quenching, electron mobilities, and photovoltaic device characteristics are also presented and indicate the ambipolar quality of these small molecule organic semiconductors.