Influence of niobium/tantalum doping on the hydrogen behavior of ZrCo(110) surface

In this paper, based on first-principles calculations, the effects of Nb/Ta modified ZrCo(110) surfaces on the adsorption, dissociation and diffusion of hydrogen are discussed. It is demonstrated that for the pure ZrCo(110) surface, H easily dissociates spontaneously, and is then captured by the holes on the surface. After entering the subsurface, H tends to fill the subsurface and continue to diffuse inward instead of escaping. After Nb/Ta doping, the maximum dissociation energy barrier of hydrogen decreases by 12.3%/37.0%, respectively. The diffusion energy barrier of H on the surface decreased by 15.8%/12.4%, and that on the subsurface decreased by 16.7%/24.1%. Charge transfer and density of states analysis showed that the bonding strength of H in the surface is improved after Nb/Ta doping. The results confirm that Nb/Ta doping can improve the hydrogen storage performance of ZrCo. (c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.