A homopolymer based on double B <- N bridged bipyridine as electron acceptor for all-polymer solar cells

Polymer electron acceptors for all-polymer solar cells (all-PSCs) are usually conjugated copolymers, which contain alternating electron-rich units and electron-deficient units. In this manuscript, we report a conjugated homopolymer (P-BNBP) based on an electron-deficient unit of double B <- N bridged bipyridine, which can be used as electron acceptor for all-polymer solar cells. P-BNBP shows low-lying LUMO energy level of -3.59 eV, high absorption coefficient of 1.6 x 10(5) L mol(-1) cm(-1) at 626 nm and moderate electron mobility of 4.37 x 10(-6) cm(2) V-1 s(-1). All-PSC devices exhibit power conversion efficiencies of 2.44%-3.04%. These results demonstrate that conjugated homopolymers are promising as electron acceptor materials for all-PSCs. (C) 2018 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.