Reducing the voltage loss of Y-series acceptor based organic solar cells via ternary/quaternary strategies

In recent years, with the emergence of non-fullerene fused-ring acceptors, power conversion efficiencies(PCEs) of organic solar cells(OSCs) have exceeded 19%. However, compared to inorganic or perovskite photovoltaic cells, a higher voltage loss has become one of the key factors limiting further improvement in the PCEs of OSCs. The ternary/quaternary strategy has been identified as a feasible and effective way to obtain high-efficiency OSCs. In this review, a brief outline is given of the key roles that guest materials played in reducing voltage losses in solar cell devices and a brief look at the future material design and the design of ternary/quaternary systems.