Electrochemical hydrogen absorption in Ni foam

An electrochemical hydrogen absorption–desorption study was carried out on Ni foam. The cyclic voltametry analysis of Ni foam in NaOH solution confirmed that there is hydrogen absorption during the electrochemical process. The cathodic peak observed during voltametry may be assigned to an adsorption pre-wave due to water electroreduction to Hab. The peak of this wave is located at a potential which is more positive than that for hydrogen evolution (ϵH2=±1.14 V). The hydride formation (implying a change in the electronic state of the H atoms) starts in the sub-surface layer, where the hydrogen atoms are close to the surface. The anodic peak observed in the voltammogram is interpreted as the hydrogen desorption maxima.