Electrochemical Activities of Oxygen-Doped Graphite Surface for V(IV)/V(V) Redox Couple

Graphite plate electrodes were treated with oxygen plasma and doped with oxygen as well as oxygen functional groups.With the treatment,the activities of graphite plate electrodes toward VO2+/VO2+ redox reaction were improved.FT-IR and EDS analysis results indicated that oxygen functional groups were introduced to the surface of graphite plates after oxygen plasma treatment.In this paper,the graphite plate treated for 20 min showed the highest activity.The average charge efficiency reached 91%,suggesting an increase of 19%,compared with that of the untreated graphite plate under a current density of 8 mA.cm-2.