Improving the hydrogen cycling properties by Mg addition in Ti-V-Zr-Nb refractory high entropy alloy

SCRIPTA MATERIALIA

卷:194

Article

Montero, Jorge¹  Ek, Gustav²  Sahlberg, Martin²  Zlotea, Claudia¹ 

[1] Univ Paris Est Creteil, ICMPE, UMR 7182, CNRS, 2 Rue Henri Dunant, F-94320 Thiais, France

[2] Uppsala Univ, Angstrom Lab, Dept Chem, Box 523, SE-75120 Uppsala, Sweden

关键词: High entropy alloys;    Hydrogen absorption/desorption cycling;    Synchrotron-XRD;    In situ neutron diffraction;   

DOI  :  10.1016/j.scriptamat.2020.113699

来源: Elsevier

【 摘 要 】

A novel high entropy alloy containing Mg and refractory elements has been prepared by mechanochemical synthetic method under inert atmosphere. The Mg0.10Ti0.30V0.25Zr0.10Nb0.25 alloy adopts a single-phase bcc lattice and can absorb hydrogen within 1 minute at room temperature forming a hydride phase with 1.7 H/M (2.7 wt.%) capacity. During the reaction with hydrogen the alloy undergoes a single-step and reversible phase transformation from bcc (alloy) to fcc lattice (hydride). The absorption/desorption cycling properties prove a small fading of the capacity for the first cycle followed by stabilization to 1.5 H/M (2.4 wt.%) for the next cycles. A simple comparison between this quinary HEA and the quaternary alloy containing only refractory elements Ti0.325V0.275Zr0.125Nb0.275 proves an important enhancement of the cycling properties by Mg addition. These insights seem to suggest that insertion of light-weighted metals such as, Mg, can guide future design of novel HEA with improved performances for hydrogen storage. (c) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free