3-Dimensional Electrode Coatings Produced by Cold Spraying Process for Hydrogen Evolution

The aim of this work is to use cold sprayed nickel electrodes for high purity hydrogen production by alkaline water electrolysis. The hydrogen produced by this method can be used as a green and renewable energy resource. Three nickel coated electrodes were produced on aluminum substrates by the cold spraying process using different spraying parameters. To improve the energy efficiency of the water electrolysis process, triple phase boundaries were enhanced by increasing the electrocatalytic active surface area of the electrodes. This was achieved by development of rough and porous electrode surfaces. Electrocatalytic activity of the electrodes towards hydrogen evolution reaction (HER) was determined by analyzing their steady-state polarization curves and electrochemical impedance spectroscopy results. Influence of the spraying parameters on electrocatalytic activity of the coatings was investigated. Scanning electron microscope (SEM), optical microscope and confocal laser microscope were used to study the microstructure and surface morphology of the coatings.