Preparation of porous TiO2-NTs/m-SnO2-Sb electrode for electrochemical degradation of benzoic acid

摘要

A novel composite porous Sb-doped SnO2 (TiO2-NTs/m-SnO2-Sb) electrode with high specific surface area and excellent electrochemical oxidation performance was fabricated through the electrodeposition method with Pluronic F127 as a templating agent. The effect of calcination temperature on the structure and electrochemical performance of the composite porous SnO2-Sb electrodes has been studied. The microstructure and composition of the electrodes were characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and N-2 adsorption-desorption. The results revealed that the electrodeposition processes with a template can improve the coating structure effectively, and an appropriate calcination temperature can improve the mesostructure and crystallinity of the SnO2. Electrochemical measurements showed that the TiO2-NTs/m-SnO2-Sb electrode had a high oxygen evolution overpotential and large electrochemical active area. The electrocatalytic performance of the TiO2-NTs/m-SnO2-Sb electrode was further analyzed in the removal of a model pollutant (benzoic acid). The corresponding kinetic constant for benzoic acid removal was greatly enhanced, and the mesostructure significantly promoted the adsorption and diffusion of benzoic acid in the TiO2-NTs/m-SnO2-Sb electrode. The effects of initial benzoic acid concentration, supporting electrolyte concentration, current density and pH on the electrochemical degradation by the TiO2-NTs/m-SnO2-Sb electrode were investigated.