Superior cycling stability of Zr–Hf–Co–Fe–Ni hydrogen isotope storage alloys achieved by hydrogen binding energy modulation

In Zr 2 Co-based alloys, Hf/Fe/Ni co-alloying tunes the interstitial hydrogen binding energy and mitigates the unit cell volume expansion, yielding the Zr 1.5 Hf 0.5 Co 0.5 Fe 0.3 Ni 0.2 alloy with excellent cycling stability.