A Simple Nonfused Ring Electron Acceptor with a Power Conversion Efficiency Over 16%†

Comprehensive Summary By simplifying the π‐bridge unit, a nonfused ring electron acceptor (NFREA) BM‐2F was designed and synthesized with several high‐yield steps. The specific molecular structure features of BM‐2F are planar molecular backbone and out‐of‐plane side chain, which is favorable for charge transport and can suppress the over‐aggregation. BM‐2F based neat and blend films display obvious face‐on molecular orientation. Specially, D18: BM‐2F based blend film can form good bicontinuous interpenetrating network. More excitingly, a power conversion efficiency of 16.15% was achieved with D18: BM‐2F based photovoltaic devices, which is the highest one based on NFREAs. Our researches manifest that NFREA is a promising direction for low‐cost and high‐performance organic solar cells.