Enhanced stability of 2D organic-inorganic halide perovskites by doping and heterostructure engineering

Abstract: Organic-inorganic halide perovskite solar cells have recently attracted much attention due to their low-cost fabrication, flexibility, and high-power conversion efficiency. The reduction from three- to two-dimension (2D) promises an exciting opportunity to tune the electronic properties of organic-inorganic halide perovskites. Here, we propose first-principles density-functional theory based route to study the effect of reduced dimensionality, impurity doping, and heterostructure engineering on energy stability, band-gap and transport properties of 2D hybrid organic-inorganic halide perovskites. We show that the energetic stability of two-dimensional organic-inorganic halide perovskites can be significantly enhanced by chemically depositing MoS2 monolayer as a precursor in the system by heterostructure engineering. While on one hand, the structures have similar and excellent transport properties as their bulk counterparts, on the other, they possess the advantage of a broad range of tunable band gaps. Our predictions will expedite future efforts (both theoretical and experimental) in the synthesis, measurements and applications of high performance perovskites.