High stability planar perovskite solar cells with inorganic charge transport layers

Perovskite solar cells based on methylammonium lead halide perovskites (abbreviated as perovskites) maintain great promise for low-cost solar-to-electricity energy conversion, due to the excellent photoelectric properties of perovskites, abundance of raw materials to synthesize perovskites, and the capability to deposit perovskites by a solution process. Significant effort has been taken to deposit high-quality perovskite thin films and, thereafter, to fabricate highly efficient perovskite solar cells. Nevertheless, the degradation of perovskite solar cells greatly limits their chance for mass production and deployment. Here, we present a device structure that can significantly improve the stability of perovskite solar cells using all inorganic charge transport layers. Specifically, solution-processed inorganic thin films, lithium (Li)-doped NiOx (Li : NiOx), and ZnO nanoparticles are used as a hole transport layer and an electron transport layer, respectively. The mechanisms behind the enhanced stability are analyzed. Solutions for further improvement in the stability and the performance of perovskite solar cells are suggested.