Hydrogen desorption from vacant MgH2

Abstract

The hydrogen desorption properties of vacant MgH2 structure were investigated both experimentally and theoretically. Ion irradiation by Ar8+ and Xe8+ ions were used to induce structural changes in MgH2. Hydrogen desorption properties were investigated by temperature programmed desorption (TPD). To obtained deeper insight in structural changes during desorption theoretical calculations were performed using DFT approach within Abinit code. Results showed that there are several mechanisms involved in desorption process, which depend on defect concentration, their position and their interaction and ordering. It has been demonstrated that the changes in near-surface area play the crucial role in desorption kinetics.