Recent Progress in Semiconducting Block Copolymers Suited for Organic Photovoltaics

Recent advances in organic photovoltaic (OPV) devices have pushed power conversion efficiencies beyond 20%; however, the precise control of bulk heterojunction morphology remains a critical challenge that urgently needs to be addressed. In this Highlight Review, we summarize recent research progress regarding semiconducting block copolymers in OPV applications, with particular emphasis on bottom-up polymer synthesis strategies. We describe the development of condensative chain polymerization and nonstoichiometric polycondensation systems, which enable the synthesis of structurally well-defined π-conjugated polymers and block copolymers. Furthermore, we discuss their applications as compatibilizers, single-component photoactive materials, and stretchable semiconducting polymers. These approaches provide new strategies for controlling nanoscale phase-separated structures and improving both device performance and mechanical durability. This review highlights the potential of semiconducting block copolymers as key materials for next-generation OPV technologies.