Voltammetric Behavior of Nickel Electrode in an Alkaline Solutiont

Abstract

Voltammetric behavior of nickel electrode in an alkaline solution has been investigated. When a nickel electrode is preserved in an alkaline solution, a film of Ni (OH)₂ is formed to grow on the electrode. The growing process of the film was found to follow a cube rule when the electrode was kept undisturbed in an alkaline solution, and to follow a paraboloid rule when continuous potential scanning was repeated in an alkaline solution. The nickel electrode covered with the Ni (OH) film was dependent on a pH of the electrolyte. At a pH higher than 11, the following empirical formula was given between the peak height i_p (μA mm^-2) and pH: i_p=k(pH-10.5), where the constant k was 9.6. The electrode potential of the Ni (OH)₂ electrode was O.196V vs. SSE in 0.1 mol dm^-3 NaOH solution. By using the Ni (OH)₂ electrode a s an indicator electrode, the electrolytic oxidation of etha nol in an alkaline solution was examined. The oxidation of ethanol took place at more positive potential than +O.5 V vs. SSE.