Ferrocene-diketopyrrolopyrrole based non-fullerene acceptors for bulk heterojunction polymer solar cells

Abstract

Herein we have investigated the photovoltaic properties of ferrocenyl tetracyanobutadiene derivatives of diketopyrrolopyrroles SM1 and SM2 as efficient non-fullerene acceptors along with a donor–acceptor (D–A) conjugated polymer P as a donor for polymer solar cells. The solar cell devices showed a maximum power conversion efficiency of 6.44% and 6.89% for the vacuum dried P:SM1 and P:SM2 active layers respectively. The solar cells based on SM2 showed higher PCE compared to SM1 which may be due to the larger values of both J_sc and FF. The results presented here demonstrate that employing ferrocene as a donor unit can provide great scope for the molecular design of highly efficient non-fullerene acceptors and provides important progress in the development of non-fullerene organic solar cells.