A planar electron acceptor for efficient polymer solar cells

A novel planar acceptor IDT-2BR was designed and synthesized. Polymer solar cells (PSCs) based on P3HT:IDT-2BR blended films gave power conversion efficiencies of up to 5.12%, which are much higher than that of PC61BM-based control devices (3.71%) and the highest values reported for P3HT-based fullerene-free PSCs.