Realization of p-type MA-based perovskite solar cells based on exposure of the (002) facet

The crystallographic orientation of perovskite crystals significantly influences their photoelectric performance and associated photovoltaic devices. The classic perovskite (MAPbI3) films based on solution processing usually suffer from chaotic orientations. The impact of preferential crystallographic orientation of MAPbI3 thin films on the carrier transport is still far from being well understood. In comparison with the (011) and (111) facets, our density functional theory results revealed that the hole carrier in the (001) facet exhibits superior carrier transport properties. Herein, the highly oriented (001) FAPbI3 could serve as growth templates and promote the (002) orientations of MAPbI3 perovskite. Furthermore, the p-type doping in MAPbI3 was obtained by controlling the amount of MAI. The (002)-dominated MAPbI3 perovskite with p-type characteristics exhibits exceptional carrier transport properties, thereby enhancing device performance.