Visible-light-activated nanocomposite photocatalyst of Cr2O3/SnO2

Abstract

Abstract Visible-light-activated Cr2O3/SnO2 nanocomposite photocatalyst was prepared by coprecipitation method and characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, N2 adsorption-desorption measurement, and UV–vis diffuse reflectance spectroscopy. The results show that phase composition, crystallite size, Brunauer-Emmett-Teller surface area, and optical absorption of samples varied significantly with the heat treatment temperatures. The Cr2O3/SnO2 photocatalyst (the molar ratio Cr to Sn is 1:2) calcined at 400°C for 2 h exhibited maximum photocatalytic activity because it has a smaller particle size of 10.05 nm and a higher surface area of 38.75 m2/g. Under visible-light (λ > 400 nm) irradiation, the degradation rate of Rhodamine B reached 98.0% in 60 min, which is about 3.5 times higher than that of the standard P25 photocatalyst.