ELECTROCATALYTIC PROPERTIES OF AMORPHOUS NICKEL BORIDE ELECTRODES FOR HYDROGEN EVOLUTION REACTION IN ALKALINE-SOLUTION

The hydrogen evolution reaction (HER) was investigated in 1 M NaOH at 70-degrees-C by steady-state polarization, and by the a.c. impedance techniques on amorphous nickel boride and nickel boride + nickel powder electrodes obtained by pressing the appropriate powders at room temperature. The influence of electrode composition on the activity was studied. The best catalytic properties were observed for an electrode composed of 10 wt.% of Ni and 90 wt.% of nickel boride. It was found that the electrodes became more catalytic for the HER after electrochemical oxidation. The hydrogen evolution reaction proceeds via the Volmer-Heyrovsky mechanism and the kinetic parameters of the process were determined. The structure and morphology of the electrodes were studied using X-ray diffraction and scanning electron microscopy.