Study of Structural, Elastic, Electronic, and Vibrational Properties of MRh2O4 (M = Cd and Zn) Spinels: DFT-Based Calculations

Abstract

Solar-assisted water splitting using photoelectrochemical cells (PECs) is one of the promising ways for the production of hydrogen to store renewable energy. Semiconducting materials are used as a key factor which controls the overall energy conversion efficiency in PECs. However, finding new semiconductors with appropriate properties (stability, efficient charge separation and transport, abundant and visible light absorption) is still a challenge for developing new materials for solar water splitting. Spinel-type structures which have suitable band gaps for visible light harvesting are promising candidates for PEC applications. In this study, first principles method within density functional theory (DFT) have been used to study the structural, elastic, electronic, and vibrational properties of MRh<inf>2</inf>O<inf>4</inf> (M = Cd and Zn) for cubic spinel phase. Present study reveals that the CdRh<inf>2</inf>O<inf>4</inf> and ZnRh<inf>2</inf>O<inf>4</inf> in spinel structure are semiconducting in nature and they also satisfy the stability criterion. Thus, studied spinels can be used as semiconductors in PEC applications. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.