Isobenzofulvene-fullerene mono-adducts for organic photovoltaic applications†
Abstract
A family of three isobenzofulvene mono-adduct fullerene derivatives are synthesized and applied as the acceptor for organic photovoltaic (OPV) cells. PTB7-based OPV cells incorporating these new fullerene derivatives show increased Voc compared to the corresponding PC60BM-based cells. The best performing derivative in this fullerene family is IC60MA-4C that contains the longest alkyl chain and that yields a power conversion efficiency of 6.5% when combined with PTB7.