Effects of transition metal (Ti, Cu, Nb, and Rh) doping into ZrCo alloys on hydrogen permeability and anti-disproportionation properties: From first-principles

The properties of ZrCo alloys strongly affect their applications in the ITER hydrogen isotope storage and transfer system (SDS). In this study, the properties of TM-doped (TM = Ti, Cu, Nb, and Rh) ZrCo alloys are studied using the density functional theory (DFT). TM dopants can improve the ductility, hardness, etc. of ZrCo alloys. The H atoms absorbed into ZrCo alloys prefer to diffuse outwards from the nearest neighbor (1nn) sites, especially for Cu/Nb dopants with lower barrier energies and higher activation properties. In b-phase ZrCoH3, hydrogen occupation of 8e si te is closely relevant to the disproportionation reaction. The substitution of Ti/Nb for Zr can effectively increase the Zr-H (8e) bond length and also decreases the volume of 8e site, which has improvement on anti-disproportionation. These results provide an atomic-level perspective on the alloying modification of mechanics, hydrogen permeability, and anti-disproportionation properties of ZrCo alloys. (c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study investigates the properties of TM-doped (TM = Ti, Cu, Nb, and Rh) ZrCo alloys using density functional theory (DFT). The results show that TM dopants can improve the ductility and hardness of ZrCo alloys, with Cu and Nb dopants having better diffusion properties. Moreover, in the b-phase ZrCoH3, hydrogen occupation is closely related to disproportionation reaction, and the substitution of Ti and Nb can improve anti-disproportionation properties.