High-performance alloy model-based ternary small molecule solar cells

There are two crucial tasks for achieving high-performance organic solar cells: increasing photon harvesting and realizing the optimized morphology of active layers. Here, two small molecules DRCN5T and DR3TSBDT as donors and PC71BM as acceptor were employed to fabricate ternary small molecule solar cells (SMSCs). The optimized ternary SMSCs delivered a power conversion efficiency of 10.16%, which was higher than that of binary SMSCs. In addition to enhanced photon harvesting, the two donors with good compatibility prefer to form alloy state in ternary active layer, resulting in efficient hole transport and continuously tunable open circuit voltage.