Stability, Structural, and Electronic Properties of Hausmannite (Mn3O4) Surfaces and Their Interaction with Water

Hausmannite (Mn3O4) is the stable phase of manganese oxides and has attracted interest due to its technological applications such as in molecular adsorption, ion exchange, catalysis, and water treatment. Hausmannite is a normal spinel structure that presents the formula A2+B23+O4, where the tetrahedral sites are occupied by Mn2+ and the octahedral sites by Mn3+ cations. The present work intends to fulfill the lack of information about the electronic and structural properties of hausmannite surfaces and their interaction with water. This is an important aspect for understanding the reaction mechanism occurring at the hausmannite–water interface. Density functional calculations have been employed to investigate the structural and electronic properties of hausmannite. Energy surfaces have been estimated for the low Miller indexes, and the water adsorption on the most favored surface was investigated in detail. The results indicate that the (001) cleavage surface is the most favored, in good agreement with th...