Acta Phys. -Chim. Sin. ›› 2003, Vol. 19 ›› Issue (09): 785-790.doi: 10.3866/PKU.WHXB20030901

• ARTICLE •     Next Articles

Electrochemical Properties of La1-xSrxNi1-yCoyO3 Bifunctional Oxygen Electrodes

Tang Zhi-Yuan;Song Shi-Dong;Liu Jian-Hua;Pan Li-Zhu;Nan Jun-Min   

  1. School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072; Chemical Department, South China Normal University, Guangzhou 510631
  • Received:2003-01-08 Revised:2003-03-17 Published:2003-09-15
  • Contact: Tang Zhi-Yuan E-mail:zytang@tju.edu.cn

Abstract: A series of novel La1-xSrxNi1-yCoyO3(x= 0, 0.1, 0.2, 0.5; y=0~1.0)perovskite oxides were prepared by sol-gel method and characterized by XRD and XPS. The activity of bifunctional oxygen electrodes made by the perovskite-type catalyst dispersed on active carbon was investigated using electrochemical impedance spectroscopy (EIS). The impedance spectra of both cathodic and anodic polarization were analyzed. The results show that the properties of electrodes are improved by doping Co3+ ions on B site because the concentration of B site ions on the catalysts surface are increased. But by doping Sr2+ ions on A site could impair the effect because the ordering level of oxygen vacancy and the electrode resistance are increased. The polarization resistance is mainly caused by the slow Nernstian diffusion and charge transfer reaction and not by concentration of adsorption of oxygen species and oxygen vacancy. So it is concluded that by increasing the concentration of B site ions on perovskite oxide surface and improving the thickness of electrolyte film the performance of oxygen electrodes could by improved.

Key words: Bifunctional oxygen electrodes, Metal-air batteries, Perovskite oxides, Electrochemical impedance spectra, Fuel cell