Understanding the effect of the double side chain fullerene derivative as third component materials on the charge dynamics and photovoltaic performance

Abstract

In this study, ternary organic solar cells (OSCs) are fabricated with the PBDB-T-2F as a polymer donor and NCBDT-4Cl as a fullerene-free acceptor, double side chain fullerene derivative NC70BA as a third component material and single side chain fullerene PC71BM as reference third component materials. The NC70BA-based ternary OSCs exhibit the highest PCE of 13.82%, which is 10% higher than that of PBDB-T-2F:NCBDT-4Cl binary OSCs and slightly higher than PC71BM-based ternary OSCs (13.24%). Detailed studies suggest that the shallow LUMO levels and double side chain for NC70BA is beneficial to broaden energy bandgap and improve compatibility, which is enhancing JSC and FF value. This work suggests that double side chain fullerene derivative NC70BA as third component materials is a promising way to finely tune the detailed photovoltaic parameters and further improve the photovoltaic performance of OSCs.