Intrinsic Carrier Mobility of Cesium Lead Halide Perovskites

Inorganic cesium-lead-halide perovskites (CsPbX3, where X = Cl, Br, and I) have recently emerged as promising semiconductors for photovoltaic and light-emitting devices. In this study, we investigate electronic and vibrational properties of CsPbX3 using the density-functional-theory calculations. We explicitly evaluate k-dependent electron-phonon scattering rates of the polar longitudinal-optical phonon modes. The transport property at room temperature is then computed based on Boltzmann transport theory within the relaxation-time approximation. The computational results identify the fundamental limit of the carrier mobility and its dependence on the halide species. Our results show that different choices of X lead to the variation in the mobility by a factor of 3 to 5 depending on the carrier concentration between 10(15) and 10(18) cm(-3). The preferred carrier type (electron or hole) in terms of the mobility also varies with X. Through the detailed analysis on the band structures and scattering rates, we provide insights into the role of halide species in the transport properties.