Recent Progress in All‐Small‐Molecule Organic Solar Cells

Abstract Active layer material plays a critical role in promoting the performance of an organic solar cell (OSC). Small‐molecule (SM) materials have the merits of well‐defined chemical structures, few batch‐to‐batch variations, facile synthesis and purification procedures, and easily tuned properties. SM‐donor and non‐fullerene acceptor (NFA) innovations have recently produced all‐small‐molecule (ASM) devices with power conversion efficiencies that exceed 17% and approach those of their polymer‐based counterparts, thereby demonstrating their great future commercialization potential. In this review, recent progress in both SM donors and NFAs to illustrate structure–property relationships and various morphology‐regulation strategies are summarized. Finally, ASM‐OSC challenges and outlook are discussed.