Effect of SnO₂‐Sb₂O₅ Interlayer on Electrochemical Performances of a Ti‐Substrate Lead Dioxide Electrode

Abstract

Abstract The Ti/SnO 2 ‐Sb 2 O 5 /PbO 2 electrode was prepared by electrodeposition method onto Ti substrate with SnO 2 ‐Sb 2 O 5 interlayer. Microstructure information of SnO 2 ‐Sb 2 O 5 interlayer and PbO 2 coating was characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). Our study shows that the titanium substrate is completely covered by the SnO 2 ‐Sb 2 O 5 solid solution interlayer and the interlayer combines the Ti substrate closely with the PbO 2 coating. The electrochemical performance of the Ti/SnO 2 ‐Sb 2 O 5 /PbO 2 electrode was studied by cyclic voltammogram (CV), electrochemical impedance spectroscopy (EIS) and accelerated life test. The results show the electrochemical activity, electrical conductivity and stability of Ti‐substrate lead dioxide electrode are increased. The deactivation process of the Ti/SnO 2 ‐Sb 2 O 5 /PbO 2 electrode was also studied by the EIS. The SnO 2 ‐Sb 2 O 5 interlayer can effectively prevent the growth of a TiO 2 insulating layer between the substrate and the PbO 2 coating during the lifetime tests, thus maintain high activity of Ti/SnO 2 ‐Sb 2 O 5 /PbO 2 electrode for 10 times longer than Ti/PbO 2 electrode without interlayer.