Stability and hydrogen adsorption properties of Mg/TiMn2 interface by first principles calculation

First principles calculations were carried out to study the stability and hydrogen adsorption properties of Mg/TiMn2 interface. The surface stability and hydrogen adsorption of TiMn2 were explored. The Mn terminated (001) is the most stable surface among the considered surfaces of TiMn2 and TiMn2 surface shows better hydrogen adsorption ability than the pure Mg surface. Two models coupling the Mg(0001) surface and the TiMn2(001) surface with different terminations were constructed to explore the Mg/TiMn2 interface. The Mg(0001)/Mn terminated TiMn2(001) with interface is much more stable than that of Ti terminated system. These two interfaces both show good hydrogen adsorption ability, in which the Mn terminated interface shows -1.62 eV of hydrogen adsorption energy. The electronic structures of the considered systems are evaluated. The negative adsorption energies of hydrogen on the surface and interface systems are further explained by the analysis of the density of states. (C) 2016 Elsevier B.V. All rights reserved.