Speaker
Description
The search for sustainable and clean alternative energy sources has recently increased interest in hydrogen storage using hydride-forming alloys. High -entropy alloys have become a topic of interest in the recent years, this is because of their potential application in hydrogen storage materials. Although numerus experimental studies have been conducted, there is still a lack in the understanding of hydrogen absorption process in the atomic level. In this study first principle calculations were employed to investigate the electronic and phase evolution during hydrogenation in Al2Ti4V6Cr3Fe alloy as well as the mechanical characteristic of the metal hydride. The lattice parameters, heats of formation, binding energy and the electronic properties of the pure and hydrogenated Al2Ti4V Cr3Fe were computed. The calculated heats of formation for hydrogenated structure were found to be negative which implies that the formation of metal hydride is thermodynamically stable and energetically favourable. The computed lattice parameters were found to be increasing with increasing the hydrogen content this suggesting the volume expansion and phase transformation. In addition, the partial density of states was calculated to investigate the electronic properties. This material is characterised as body-centred cubic. The maximum hydrogen storage capacity of Al2Ti4V6Cr3Fe is predicted to be 4.1 wt%. These calculations demonstrate that the Al2Ti4V6Cr3Fe high entropy alloy could be a promising hydrogen storage material.
| Abstract Category | Materials Physics |
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