Hydrogen occlusion behaviors of ZrVFe alloys under mild hydrogen pressures and lowering of their hydrogen desorption temperatures

Four kinds of ZrVFe alloys with the C14 Laves phase structure had high hydrogen storage capacity under mild pressures, and those alloys would be promising for widespread application such as recovery of hydrogen derived from water splitting. Addition of titanium to ZrVFe lowered hydrogen desorption temperatures through increase of equilibrium pressures. Substitution of ferrovanadium for vanadium did not deteriorate hydrogen occlusion performance of ZrVFe, and provided with lower cost alloys. Another way to reduce the cost would be elimination of purifying step of vanadium prepared by the thermite process, but remaining aluminum proved to bring about lower hydrogen capacity, as evidenced by comparative experiments including a ZrVFe alloy with aluminum intendedly added. Every alloy had fairly good cycling durability except the one contaminated with aluminum.