Ultrasonic aerosol spray-assisted preparation of TiO2/In2O3 composite for visible-light-driven photocatalysis

A TiO2/In2O3 composite photocatalyst has been prepared by using a facile ultrasonic aerosol spray (UAS)-assisted method. Results from scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N2 adsorption–desorption measurements reveal that the as-prepared TiO2/In2O3 composite exhibits a porous structure and spherical morphology. The diameter ranges from tens of nanometers to several micrometers. According to the UV–vis diffuse reflectance spectra, the TiO2/In2O3 composite shows good visible-light absorption ability. The photocatalytic activity of the samples was evaluated by the decomposition of organic dyes in aqueous solutions under visible-light irradiation. All the composite samples show excellent photocatalytic performance. The effect of In2O3 content on the photocatalytic activity was also investigated. The best photocatalytic activity results from the TiO2/In2O3 sample with Ti:In molar ratio of 100:1. The UAS-assisted method can also be applied for the preparation of other composite semiconductor materials. It provides a general approach for scaling up the production of photocatalysts for practical applications.