BaZrSe 3: Ab initio study of anion substitution for bandgap tuning in a chalcogenide material

Recently, transition metal perovskite chalcogenide materials have been proposed as possible candidates for solar cell applications. In this work, we provide accurate theoretical calculations for BaZrS 3 and two phases of SrZrS 3, which have been recently synthesized and their optical properties elaborated. In this study, we consider the substitution of S in BaZrS 3 with Se to form BaZrSe 3. Evolutionary methods are used to find the optimal structure of this compound, and accurate calculations of its optoelectronic properties are presented. Using phonon frequency calculations and ab initio molecular dynamics, we assess the stability of this compound. We find that BaZrSe 3 is likely to be stable under typical conditions, with a low bandgap and high optical absorption coefficients. This suggests that BaZrSe 3 could be useful for solar cell applications.