Abstract: The redox reaction processes and Raman spectra of reaction products of cobalt electrodes in 30% KOH+1% LiOHsolution were studied by using in-situ Confocal Microprobe Raman Spectroscopy. It is shown that the oxidation reaction at -0.64 Vcan be ascribed to the formation of Co(OH)₂ and CoO. Co₃O₄ was formed with increasing the potential, and Co₃O₄, CoOOH and CoO₂ form composite oxides surface layer in positive potential region. In the course of potential sweeping from the positive to the negative, the higher valent oxides were reduced to Co₃O₄ and Co(OH)₂ successively, and they were reduced to Co finally. From the Raman spectra at different potentials of cobalt electrodes, it is proposed that the redox reactions are continuous processes with the changing of potentials, and the surface layer of cobalt electrode is composed of composite oxides.

Key words: Cobalt electrode, Redox reaction, In-situ confocal microprobe Raman spectroscopy