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

A novel platinum complex-based electron acceptor Pt-Y is synthesized, exhibiting long exciton life times, well-compatibility with other acceptors and highly crystallized tendency, which can be successfully applied into ternary organic solar cells with a high efficiency of 19.2%.

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.