On the poisoning effect of O2 and N2 for the Zr0.9Ti0.1V2 hydrogen storage alloy

► XPS analysis clarifies the poisoning process of Zr0.9Ti0.1V2 in gaseous impurities. ► The poisoned alloy loses capacity as the oxidized surface blocks hydrogen. ► The passivated layer accounts for the regeneration of the poisoned alloy. ► The results provide a technical guidance to optimize properties of Zr-based alloys.