The First-principles Study of Microscopic and Electronic Structure of CsBi3I10

Abstract

The hybrid organic-inorganic perovskite materials have received a lot of attention in the fields of solar cell applications due to their excellent electrical and optical properties with simple solution process ability and low cost. But, the highly-toxic lead (Pb) is mainly used as light absorber in the most of the high efficient solar cell materials. Due to the issues on the environmental concerns, other materials such as Sn, Ge, Bi are suggested as lead replacement. Among lead-free materials, Sn-based ones have the highest efficiency, but easy and rapid oxidations from Sn2+ to Sn4+ lead to the structural instabilities in air. Ge-based ones are expansive and are difficult to make due to tricky process while they have appropriate band gaps for the solar cell applications. In this view, Bi-based perovskite materials are emerged as good candidates because they are low-toxic and are stable in air. Recently, Johnasson et al. experimentally reported high efficient Bi-based material of CsBi3I10, but no detailed theoretical studies have been investigated yet. Therefore, it is crucial to understand the reason why CsBi3I10 shows the high efficiency as compared to other Bi-based materials for the development of the next generation solar cells. In this presentation, we will study about the microscopic and electronic structure of CsBi3I10 using the first-principles pseudopotential total energy calculations based on the density functional theory (DFT).