Improving the performance of solar cells by optimizing the interface of SnO2/perovskite layer using sodium citrate

Interface engineering is an important means of modifying perovskite solar cells (PSCs). In this paper, a strategy for modifying the SnO2/perovskite interface transport layer using sodium citrate (SC), an organic sodium salt, was proposed. The optimal power conversion efficiency was 22.55%, 9.3% higher than that of devices without SC modification. The open circuit voltage (Voc) reaches a respectable 1.20 V. This method enhances the conductivity of thin SnO2 films with inert photocatalytic performance, improves the crystallinity of perovskite, and increases the grain size, thereby meliorating the performance and stability of PSCs.