Electrode Materials for Hydrogen Production by Alkaline-Water Electrolysis Powered by Renewable Energy Sources

Effectiveness of electrode materials for electrolizers working with renewable energy sources are discussed. The electrochemical behavior of low-alloy chrome-molybdenum-vanadium steel (12Cr1MoV) in a 5 mol.L⁻¹ sodium hydroxide solution is presented and compared with steel of ordinary quality (Steel 3) and nickel that are used in electrolyzers for producing hydrogen. Weight loss tests show that the chrome-molybdenum-vanadium steel is more corrosion-resistant in the tested environment than Steel 3. Overvoltage of oxygen evolution reaction on 12Cr1MoV steel under galvanostatic conditions of 200 m.Arcmr⁻² is 40 mV lower than on Steel 3 and 150 mV lower than on nickel. Chrome-molybdenum-vanadium steel is perspective to replace Steel 3 in alkaline water electrolysis both as electrode material and as substrate for different catalytic coatings. Multilayer coating [(Ni-Cu)/(Mi-Mi(OH)2)]n is proposed for use in alkaline electrolysis of water and in fuel cells in systems with renewable energy sources. Proposed electrodes are suitable for use in electrolyzes powered by renewable energy sources as they show lower corrosion rate during pauses and load changes.