First-principles study of photovoltaics and carrier mobility for non-toxic halide perovskite CH3NH3SnCl3: theoretical prediction

Abstract

Promising candidates in this respect are organometal perovskites ABX₃, which have been intensely investigated during the last years. In this paper, we calculate the crystal structures, optical properties and carrier mobility for three phases of non-toxic perovskite halide CH₃NH₃SnCl₃ by applying density functional theory with the nonlocal van der Waals (vdW) correlation. The results show that CH₃NH₃SnCl₃ has superior performance in terms of its optical absorption coefficient, which reaches as high as 10⁵ cm⁻¹ and has proven itself to be a perfect solar light harvester. Most importantly, the results of intrinsic carrier mobility of CH₃NH₃SnCl₃ show that the electron mobility of the triclinic phase can achieve a large magnitude of 1700 cm² V⁻¹ s⁻¹, which is mainly due to the small effective mass. We ascribe the superior photoelectric property to the ferroelectricity, which may be caused by the distorted octahedral SnCl₆⁻.