Preparation and characterization of PbO₂electrodes doped with TiO₂and its degradation effect on azo dye wastewater

In this paper, P25-TiO2doped PbO2electrodes based on the Ti/SnO2-Sb substrate were prepared by the co-deposition method. The XRD results justified that P25 particles have been successfully doped into the pbo2layer. The surface morphology of prepared electrodes was examined by scanning electron microscopy. It was found that the doped pbo2electrode has a more compact and dense surface with no flaw or crack on it, comparing to those of undoped electrodes. The accelerated life test demonstrated that the doped pbo2electrode has a better stability than the undoped one. A significant synergetic effect was observed in the organic degradation test under illumination using the doped pbo2electrode, as evidenced by linear scanning voltammetry. Acidic condition (pH < 7) induces a better performance in methyl orange degradation due to a higher adsorption of methyl orange on the TiO2surface. All the doped electrodes with different TiO2doping levels presented high removal efficiency under irradiation, though the increase in service lifetime was not observed. A TiO2doping amount of 5 g.L-1is established as the optimal dosage for preparing the electrode for the higher performance in both the accelerated life and the degradation tests.