Highly Efficient Inverted D:A₁:A₂ Ternary Blend Organic Photovoltaics Combining a Ladder-type Non-Fullerene Acceptor and a Fullerene Acceptor

Abstract

A formylated benzodi(cyclopentadithiophene) (BDCPDT) ladder-type structure with forced coplanarity is coupled with two 1,1-dicyanomethylene-3-indanone (IC) moieties via olefination to form a non-fullerene acceptor, BDCPDT-IC. The BDCPDT-IC, as an acceptor (A1) with broad light-absorbing ability and excellent solution processability, is combined with a second PC71BM acceptor (A2) and a medium band gap polymer, PBDB-T, as the donor (D) to form a ternary blend with gradient HOMO/LUMO energy alignments and panchromatic absorption. The device with the inverted architecture using the D:A1:A2 ternary blend has achieved a highest efficiency of 9.79% with a superior Jsc of 16.84 mA cm–2.