Oxygen evolution on Co3O4 and Li-doped Co3O4 coated electrodes in an alkaline solution

The oxygen evolution reaction "OER# was investigated at 59>C in 04 wt) NaOH solution on Co2O3\ Li!doped Co2O3 and perovskite!type oxide "LaNiO2# electrodes[ Cobalt and Li!doped cobalt oxides were obtained by di}erent preparation techniques and were applied to chemically!pickled nickel plates[ The obtained phases were structurally characterized by X!ray powder di}raction[ The electrodes were subjected to electrochemical measurements\ before and after elec! trochemical ageing "10 days\ 049 mA cm−1#[ The correlation between the coating preparations and their electrocatalytic activity was investigated[ The e.ciency of the studied electrodes seems to depend on the preparation method[ Two Tafel slopes for the OER were observed in most cases[ This behaviour was interpreted on the basis of a change in the valence state of the surface oxide[ Þ 0888 International Association for Hydrogen Energy[ Published by Elsevier Science Ltd[ All rights reserved[