A Platinum Complex‐Based Dimerized Electron Acceptor for Efficient Organic Solar Cells

Abstract Metal–organic complexes have demonstrated excellent performance in organic light‐emitting diodes, yet their potential in organic solar cells (OSCs) remains underexplored. In this study, a novel metal–organic complex, Pt‐Y, which features a platinum core connected to Y‐acceptor arms, for application in OSCs is designed and synthesized. The dimerized Pt‐Y acceptor is prepared through straightforward reactions, with the key precursor linking the platinum metal and Y‐acceptors synthesized through Sonogashira coupling. Steady‐state and transient photoluminescence measurements revealed that Pt‐Y exhibits distinct singlet and triplet states with microsecond lifetimes—significantly longer than the nanosecond lifetimes of Y‐acceptors without the metal. Incorporating Pt‐Y as a third component in ternary OSCs has resulted in a remarkable efficiency of 19.2%. Further morphological analysis and transient absorption measurements indicate that the dimerized Pt‐Y displays excellent miscibility with the Y‐acceptor, leading to minimal phase separation and the formation of fibrillar structures. These structures enhance charge separation and transport while reducing charge recombination. This work presents a facile approach to developing metal–organic complexes with exceptional photovoltaic performance in OSCs.