Preparation and characterization of Ti/SnO2-Sb2O3-Nb2O5/PbO2 thin film as electrode material for the degradation of phenol

In this work, a novel electrode of titanium substrate coated with mixed metal oxides of SnO2, Sb2O3, Nb2O5 and PbO2 was successfully prepared using thermal decomposition and electrodeposition. The surface morphology and the structure of the prepared thin film were characterized by scanning electronic microscopy (SEM) and X-ray diffraction (XRD), respectively. Experimental results showed that the structure of the prepared electrode might be described as a Ti/SnO2-Sb2O3-Nb2O5/PbO2 thin film and its surface was mainly comprised pyramidal-shape beta-PbO2 crystals. The modified electrode had higher oxygen evolution potential than that of other PbO2 modified electrodes. Electrocatalytic oxidation of phenol in aqueous solution was studied to evaluate the potential applications of this electrode in environmental science. The phenol removal efficiency in an artificial wastewater containing 0.50 g/L phenol could reach 78.6% at 20 deg C and pH 7.0 with an applied electricity density of 20 mA/cm2 and treatment time of 120 min. When 21.3 g/L chloride was added to this wastewater, the removal efficiency could reach to 97.2%.