Electrocatalytic Properties and Modification of La1-xSrxCoO3 (x=0, 0.2, 0.4, 0.6, 0.8) Perovskite Oxide

The Sr-doped perovskite oxides La1-xSrxCoO3 (x=0, 0.2, 0.4, 0.6, 0.8), as the electrocatalyst for bifunctional oxygen electrode, were synthesized by sol-gel method. The test results show that Sr-doped La1-xSrxCoO3 has higher electrocatalytic activities than LaCoO3. In addition, La0.6Sr0.4CoO3 reveal excellent catalytic activity for the oxygen evolution reaction and oxygen reduction reaction, reaching a maximum of 0.244 A.cm(-2) (at 0.6 V vs Hg/HgO) and 0.303 A.cm(-2) (at 1 V vs Hg/HgO). In order to further improve the catalytic activity of the catalyst, alpha-MnO2 nano-wires as bi-functional catalyst was prepared by hydrothermal synthesis and added into the La0.6Sr0.4CoO3. The activities of bi-functional catalysts of alpha-MnO2/La0.6Sr0.4CoO3 were markedly superior compared with a-MnO2 or La0.6Sr0.4CoO3 perovskite oxide when the mass fraction of 40% alpha-MnO2, demonstrating a synergistic effect, which was responsible for the improvement of electrochemical catalytic activity and stability of the bifunctional oxygen electrode.