China Nonferrous Metallurgy

Hydrogen storage alloys can significantly alleviate the problem of component leaching during intermittent power supply from electrolysis water hydrogen production using wind energy and solar energy. Compared with rare earth-based hydrogen storage alloys, vanadium-based solid solution hydrogen storage alloys have a unique reversible hydrogen absorption and desorption process at room temperature, which can more effectively prevent the leaching of electrode components during power outage.This paper starts from two aspects: enhancing the anti-intermittent power supply ability of the electrode and reducing the overpotential of hydrogen evolution. Using vanadium, titanium and nickel metal powders as raw materials, vanadium-based porous alloy hydrogen evolution materials were prepared by powder solid-state sintering method. The influence of the preparation process conditions on the surface morphology and hydrogen evolution catalytic ability of the materials was investigated.The results show that the thermodynamic calculation results indicate that the Ti2-Ni phase disappears at a temperature of 700℃, while the Ti-Ni phase reaches its peak content of approximately 26%. At temperatures ranging from 950℃ to 1000℃, the Ti-Ni phase melts and forms a liquid phase. Under the conditions of adding 30% ammonium bicarbonate as the pore-forming agent, a forming pressure of 150MPa, a sintering temperature of 950℃, and a holding time of 4 hours, the prepared vanadium-based alloy has good performance, with a porosity of 52.99% and an open porosity of 32.56%. This can provide more active sites for the hydrogen evolution reaction;The hydrogen evolution overpotential of this vanadium-based alloy is 268mV, the charge transfer resistance is 92.7Ω, and the electrochemical active surface area (ECSA) is 5.69cm2. The hydrogen evolution overpotential is lower than that of the iron sheet electrode and the copper sheet electrode.