Cyclic voltammetric studies of pure and doped films of cobalt hydroxide in 1M potassium hydroxide

Cyclic voltammetric studies of electrosynthetically prepd. pure and doped thin films of cobalt hydroxide (on a platinum foil substrate) in 1M KOH show that Co(OH)​2 undergoes a quasi-​reversible redox reaction between a nearly quadrivalent black oxidic phase and a trivalent brown bronze-​like phase. The coulombic efficiency is 60​%. A common scheme is proposed for the electrode reactions of oxide electrodes in alk. media, namely: MII(OH)​2 .dblharw. HMIIIO2 .dblharw. MIVO2, where M = Mn, Co, Ni. The three metals execute different steps in this two-​electron redox reaction, either reversibly or qu..