The hydrogen evolution reaction on NIPx alloys

The hydrogen evolution reaction (HER) was studied on NIP, electrodes contai ning 15-27 at% P prepared by electrodeposition. The amount of P in the allo y varied with deposition potential. The activity of the electrodes was depe ndent on the P concentration, and the formation of a passive film. The P in the deposited Ni alters the reaction mechanisms for the HER significantly. This is probably caused by the absorption of hydrogen into the NiPx alloy. A potential step, from the cathodic to the anodic region, gave information about the diffusion of absorbed hydrogen, A correlation between the activi ty of the electrodes, and the amount of absorbed hydrogen was found the mos t active electrodes also absorbed the largest amount of hydrogen. (C) 2000 International Association for Hydrogen Energy. Published by Elsevier Scienc e Ltd. All rights reserved.