A nonfullerene acceptor for wide band gap polymer based organic solar cells†
Abstract
A new 1,8-naphthalimide based planar small molecular acceptor and two benzothiadiazole based wide band gap (WBG) polymer donors P1 and P2 were synthesized for nonfullerene organic photovoltaic cells (OPVs). Devices based on fluorinated polymer P2 achieved a highly improved PCE of 3.71% with an open circuit voltage (Voc) of 1.07 V, which is beyond the currently known levels for nonfullerene OPVs with the Voc higher than 1 V.