Characterization of a Ti/SnO2-Sb/Fe-PVP-PbO2 Electrode Deposited from Methanesulfonate Bath and Application in Electrocatalytic Degradation of MO

Ti/SnO2-Sb/PbO2 anodes were electrodeposited from methanesulfonate-based baths, and the effect of dopants such as PVP and Fe on the surface morphology, phase composition, electrocatalytic activity and stability was investigated. It is revealed that the inclusion of Fe effectively enhances the stability of PbO2 anode, while PVP can significantly improve its electrocatalytic activity. The Fe,PVP-codoped anode, Ti/SnO2-Sb/Fe-PVP-PbO2, exhibits the higher stability and electrocatalytic activity compared to the respective inclusion of Fe and PVP. The gradation efficiency of methyl orange (MO) on the Ti/SnO2-Sb/Fe-PVP-PbO2 anode is affected by the applied current density and the initial MO concentration. During degradation, the azo structure of MO is firstly cleaved, resulting in the rapid decolorization of solution. Demethylated MO and the anion of sulfanilic acid are detected as intermediates, and thus a plausible pathway of MO degradation is proposed.