Preparation and Photocatalytic Performance of Hollow Spherical TiO2/Cu2O Composites

Abstract

The anatase phase titanium dioxide sols were prepared by hydrothermal method using titanium sulfate as the titanium source. Copper acetate monohydrate was used as the copper source, cubic phase Cu2O with matched bandgap TiO2 was introduced to synthesize hollow spherical nano-TiO2/Cu2O composites by precipitation method. The powder samples were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), specific surface area testing (BET), X-ray electron spectroscopy (XPS) and ultraviolet and visible spectrophotometry (UV–Vis) diffuse reflectance spectroscopy analysis using methyl orange (MO) solution as indicator. The results showed that the introduction of Cu2O did not affect the physical phase of TiO2. Titanium dioxide was a shuttle-shaped nanorod with an average particle size less than 20[Formula: see text]nm, Cu2O was a sphere with an average particle size greater than 400 nm. TiO2 loading results in smaller particle size, larger specific surface area, thinner spherical walls, increased hollowness, and improved adsorption and photocatalytic properties of spherical Cu2O. The optimum Ti content of TiO2/Cu2O nanocomposite was 4.0 wt.%, the maximum specific surface area of TiO2/Cu2O sample was 90.57 m2/g with particle size less than 150 nm. When TiO2/Cu2O sample with Ti content of 4.0[Formula: see text]wt.% was used as photocatalyst, the adsorption effect was 66.2% under the dark reaction at 60[Formula: see text]min, the degradation effect was 91.2% under visible light irradiation at 120[Formula: see text]min. The adsorption and photocatalytic performance were excellent when the TiO2/Cu2O sample with Ti content of 4.0[Formula: see text]wt.% was used as the photocatalyst. This work provides an effective method for photocatalytic treatment of waste liquids.