Hydrogen interaction with Mn-doped Zr2Fe (101) surface: A DFT study. (5th June 2022)

• Record Type: Journal Article
• Authors: Xiao, Kela; Zhou, Linsen; Kong, Xianggang; Luo, Deli; Song, Jiangfeng
• Is Part Of: International journal of hydrogen energy. Volume 47:Number 48(2022)
• Page Start: 20932
• Page End: 20941
• Publication Date: 2022-06-05
• Subjects: Zr2Fe alloy -- Mn-doped Zr2Fe alloy -- H2/H dissociation and adsorption mechanisms -- Density functional theory; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.04.203
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: The metal getter materials play a pivotal role in the treatment of tritium-containing waste gas, which is one of the most important tasks in fusion reactions, owing to the characteristics of no tritiated water product and easy recovery by the form of reversible metal hydrides. As the most promising and attractive hydrogen isotopes trapping materials for metal getters, Zr2 Fe alloy has the advantages of low thermal neutron absorption, high corrosion resistance, fast hydrogen absorption rate, and high absorption efficiency, which have attracted great attention. Though pristine/Mn-doped Zr2 Fe have been widely used to trap tritium from nitrogen and inert gases, an atomic-scale description of the inherent interaction mechanism between hydrogen and pristine/Mn-doped Zr2 Fe surface is still lacking. Herein, density functional theory (DFT) calculations were employed to study the effect of doping Mn on the adsorption, dissociation and diffusion of hydrogen on the Zr2 Fe(101) surface. It is found that the number of adsorption sites and adsorption strength of hydrogen increase when a Fe atom is substituted by a Mn atom. In addition, the dissociation and diffusion barriers of hydrogen are lowered on the Mn-doped surface. The electronic structure analysis shows that the adsorptions of hydrogen molecules cause more electron transfer to the surfaces and there exists strong interaction between hydrogen and doping Mn. Consequently, this should enhance the hydrogen storage performance of Zr2 Fe alloy, due to the surface adsorption and diffusion of hydrogen being improved by doping Mn. All these findings can provide insightful guidance for future research to improve the hydrogen storage capacity of Zr-based alloy materials and the design of metal getters for tritium-containing waste gas treatment. Highlights: H2 adsorption and dissociation on pristine/Mn-doped Zr2 Fe (101) surfaces are studied. Mn-doping facilitates the H2 adsorption and dissociation on Zr2 Fe (101) surface. Mn-doping decreases the energy barrier of hydrogen diffusion on Zr2 Fe (101) surface. Mn-doping is beneficial to improve the hydrogen storage properties of Zr2 Fe alloy.