Electrochemical activation of Raney Nickel air electrodes

We study slow and nearly reversible processes of reduction, hydride formation and oxidation in Raney-Ni air electrodes in concentrated KOH solutions. A labile β-NiH phase is formed upon prolonged cathodic polarization under H2 atmosphere. Repeated cathodic/anodic cycles enhance hydrogen intake and induce surface modifications of the Raney-Ni grains. ©The Electrochemical Society.