The Application of Y Series Acceptor-Based Double-Cable Polymers in Single-Material Organic Solar Cells

The development of efficient and stable organic photovoltaic (OPV) systems for commercial applications has long been a primary objective. While single-component material systems have demonstrated promising operational and thermal stability, their efficiency still lags behind that of multicomponent bulk heterojunction devices due to limitations in scarce building blocks, complex synthesis processes, and challenges in controlling morphology. In this work, we present a novel approach by introducing a fused-ring electron acceptor as a pendant segment, which offers new possibilities for the development of double-cable single-component copolymers. This innovative strategy not only broadens their spectral absorption but also simplifies their synthesis complexity. Through careful adjustment of molecular weight, we achieved an outstanding power conversion efficiency of 9.35% and a minimized energy loss of 0.517 eV, which is one of the best results reported for structure well-defined double-cable copolymer-based OPVs. Impressively, the designed double-cable polymers exhibit excellent photo, thermal, and mechanical stabilities, further highlighting their potential for practical applications.