CVs of electrodeposited nickel electrodes in aqueous MOH (M =Li+, Na+, K+) are shown in Fig. 1a. It is obvious that the cathodic and anodic peak potentials of spontaneous formed Ni(OH)2 shift to positive slightly in the three alkali metal hydroxides with an order of KOH b NaOH b LiOH, which is also evidenced by Anaissi et al.[20], variation of potentials in these three electrolytes might be caused by the possible interaction between OH− and alkali metal cations. A scan rate study was carried out to understand the electrochemical behavior of oxidized Ni films in strong alkaline medium,and scan rates dependent cathodic and anodic peak currents areshown in Fig. 1b. A linear relationship can be observed in Fig. 1b at