Enhancement of vanadium addition on hydrogen storage properties of high entropy alloys TiZrFeMnCrVx

Abstract

High Entropy Alloys (HEAs) have attracted increasing attention due to their unique characteristics, of which the lattice distortion property is particularly beneficial for hydrogen storage. Herein, we prepared the TiZrFeMnCrV HEAs with different V contents and elucidated the effect of V on the hydrogen storage properties. The TiZrFeMnCrVx (x = 0.5, 1.0, 1.5, 2.0 at%) alloys rapidly absorb 90% of their hydrogen storage capacity within 76 s at 30 °C. Among the alloys, all the three alloys TiZrFeMnCrVx (x = 1.0, 1.5, 2.0 at%) exhibit higher hydrogen absorption properties, which absorb 1.91, 1.93 and 1.91 wt% of hydrogen at 30 °C, respectively. Among them, the TiZrFeMnCrVx (x = 1.0 at%) alloy shows the best dehydrogenation performance, starting to release hydrogen at 151.33 °C and terminating at 346.36 °C. Meanwhile, the TiZrFeMnCrVx (x = 1.0 at%) exhibits remarkable cycle stability and displays a reversible gravimetric capacity of 98% after 15 cycles.