Mutual impact of crystal volume and heat of alloy formation on hydride stabilities in Zr(PdxCr1−x)2 and similar intermetallics

• Published in: Journal of alloys and compounds 2020-01, Vol.814, p.152268, Article 152268
• Main Authors: Babai, D., Bereznitsky, M., Shneck, R.Z., Jacob, I.
• Format: Article
• Language: English
• Subjects: Correlation with heat of alloy formation and unit cell volume; Destabilization; Hydrides; Hydrogen absorbing materials; Hydrogen absorption in the “hydrogen-inert” ZrPd2; Hydrogen storage; Intermetallic compounds; Palladium; Shear modulus; Stability; Unit cell; Zirconium; Zr(PdxCr1−x)2 pseudobinary intermetallic compounds
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.152268

Hydrides of Zr(PdxCr1−x)2 pseudobinary compounds (x = 0.05, 0.1, 0.175) exhibit slight destabilization and more sloped hydrogen plateau pressures with the increase of the palladium content. The former feature conforms to the rule of reverse stability but violates the trend of increased hydride stability upon increasing the unit cell intermetallic volume. A combination of the two effects, the heat of alloy formation and the crystal volume, shows better correlation with the hydride stabilities than considering separately each property. Hydrogen absorption is found in ZrPd2 at ∼60 atm and associated with its moderate shear modulus. •Pd substitution slightly destabilizes the hydrides in the Zr(PdxCr1-x)2 system, 0 ≤ x ≤ 0.175.•Heats of alloy formation and cell volumes demonstrate a mutual impact on hydride stabilities.•The “hydrogen-inert” ZrPd2 compound is found to absorb hydrogen at 60 atm.•A moderate shear modulus opens the gate for hydrogen absorption.•A high shear modulus shuts the gate for hydrogen absorption.