Improving the Stability of Halide Perovskite Solar Cells Using Nanoparticles of Tungsten Disulfide

Halide perovskites-based solar cells are drawing significant attention due to their high efficiency, versatility, and affordable processing. Hence, halide perovskite solar cells have great potential to be commercialized. However, the halide perovskites (HPs) are not stable in an ambient environment. Thus, the instability of the perovskite is an essential issue that needs to be addressed to allow its rapid commercialization. In this work, WS₂ nanoparticles (NPs) are successfully implemented on methylammonium lead iodide (MAPbI₃) based halide perovskite solar cells. The main role of the WS₂ NPs in the halide perovskite solar cells is as stabilizing agent. Here the WS₂ NPs act as heat dissipater and charge transfer channels, thus allowing an effective charge separation. The electron extraction by the WS₂ NPs from the adjacent MAPbI₃ is efficient and results in a higher current density. In addition, the structural analysis of the MAPbI₃ films indicates that the WS₂ NPs act as nucleation sites, thus promoting the formation of larger grains of MAPbI₃. Remarkably, the absorption and shelf life of the MAPbI₃ layers have increased by 1.7 and 4.5-fold, respectively. Our results demonstrate a significant improvement in stability and solar cell characteristics. This paves the way for the long-term stabilization of HPs solar cells by the implementation of WS₂ NPs.