Effects of IrO2 interlayer on the electrochemical performance of Ti/Sb-SnO2 electrodes

In this work, the Ti/Sb-SnO2 and Ti/IrO2/Sb-SnO2 electrodes have been successfully fabricated by coating pyrolysis method. The effects of introducing IrO2 interlayer were analyzed systematically by X-ray diffraction (XRD), scanning electron microscopy (SEM), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and accelerated service life test. Our results showed that the presence of IrO2 interlayer on the Ti substrate promoted the electrodes' property effectively. In contrast with the traditional Ti/Sb-SnO2 electrode, Ti/IrO2/Sb-SnO2 electrode possesses smaller grains and more compact morphology structure. Then the changes of oxygen evolution potential (OEP) and charge transfer resistance (Rct) on the electrodes were discussed. Anodic stability test results showed that the introduction of IrO2 interlayer in the oxide coating produced a significant increase in stability. The accelerated service life of Ti/IrO2/Sb-SnO2 electrode was almost 30 times longer than that of Ti/Sb-SnO2 electrode.