Evaluation of hydrogen storage performance of ZrTiVNiCrFe in electrochemical and gas-solid reactions.

In the present study, the hydrogen storage performance of multi-principal-component ZrTiVNiCrFe alloy produced through rapid solidification has been examined by electrochemical methods and gas-solid reactions. XRD and EBSD analyses reveal the hexagonal Laves phase structure (type C14) with average grain size of 300 nm and root-mean-square microstrain of 0.19%. Cyclic voltammetry and electrochemical impedance spectroscopy analyses in the hydrogen sorption/desorption region give insight to the sorption/desorption kinetics and the change in the desorption charge in terms of the applied potential. The pressure-composition isotherms measured in course of gas-solid reaction confirm the hydrogen storage capacity reaching 1.6 wt% at the first hydrogenation at room temperature, then reducing to 1.3–1.4% during subsequent cycling. According to the calorimetric titration study, there is a significant hysteresis primarily caused by the non-equilibrium character of the hydrogenation process. • Single phase ZrTiVNiCrFe has been synthesized by melt spinning. • Reversible hydrogenation was confirmed by gas-solid and electrochemical methods. • Maximum hydrogen capacity at room temperature reaches 1.6 wt%. • Hydrogen desorption enthalpy of 38 kJ/mol H 2 was evaluated from calorimetric measurements. [ABSTRACT FROM AUTHOR]