Electrochemical hydrogen charge and discharge properties of La0.1 Sr0.9Co1-yFeyO3-δ (y=0, 0.2, 1) electrodes in alkaline electrolyte solution

In this work, we studied the hydrogen storage properties of some La0.1Sr0.9Co1-yFeyO3-delta perovskite oxides for the application in Ni-H batteries. Sr-doped La0.1Sr0.9FeO3-delta (LSF), La0.1Sr0.9CoO3-delta (LSC) and La0.1Sr0.9Co1-yFeyO3-delta (LSCF) oxides were synthesized by conventional solid state method and were selected as anode materials for Ni-H battery. Their electrochemical hydrogen charge/discharge properties of oxide electrodes were investigated and exchange current density and proton diffusivity were calculated using linear polarization measurement and the potential-step method, respectively. X-ray photoelectron spectroscopy (XPS) analysis was used to show the changes in oxidation states of transition metal ions during charging/discharging process. The proton diffusion rates for LSF, LSC and LSCF were 6.73 x 10(-17), 1.45 x 10(-16) and 2.16 x 10(-16) cm(2) s(-1), respectively. (C) 2013 Elsevier Ltd. All rights reserved.