Solubility of Hydrogen in a WMoTaNbV High-Entropy Alloy

• Published in: Materials Vol. 17; no. 11; p. 2574
• Main Authors: Liski, Anna, Vuoriheimo, Tomi, Byggmästar, Jesper, Mizohata, Kenichiro, Heinola, Kalle, Ahlgren, Tommy, Tseng, Ko-Kai, Shen, Ting-En, Tsai, Che-Wei, Yeh, Jien-Wei, Nordlund, Kai, Djurabekova, Flyura, Tuomisto, Filip
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 27-05-2024; MDPI
• Subjects: Activation analysis; Activation energy; Alloys; Annealing; Density functional theory; Density functionals; deuterium; Energy; Enthalpy; Entropy; high entropy alloy; High entropy alloys; Hydrogen; Hydrogen isotopes; Hydrogen storage materials; Intermetallic compounds; Metals; Sensors; Solubility; solution enthalpy; Specific gravity; Spectrum analysis; Temperature; high entropy alloy; elastic recoil; solution enthalpy; deuterium; density functional theory; activation energy; metals; hydrogen
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17112574

The WMoTaNbV alloy has shown promise for applications as a solid state hydrogen storage material. It absorbs significant quantities of H directly from the atmosphere, trapping it with high energy. In this work, the dynamics of the absorption of hydrogen isotopes are studied by determining the activation energy for the solubility and the solution enthalpy of H in the WMoTaNbV alloy. The activation energy was studied by heating samples in a H atmosphere at temperatures ranging from 20 °C to 400 °C and comparing the amounts of absorbed H. The solution activation energy EA of H was determined to be EA=0.22±0.02 eV (21.2 ± 1.9 kJ/mol). The performed density functional theory calculations revealed that the neighbouring host atoms strongly influenced the solution enthalpy, leading to a range of theoretical values from -0.40 eV to 0.29 eV (-38.6 kJ/mol to 28.0 kJ/mol).