Studying the preparation of pure Bi12SiO20 by Pechini method with high photocatalytic performance

The sillenite compound Bi12SiO20 was synthesized via Pechini sol–gel method. Composition, crystallinity, microscopic appearance, and optical properties of samples were characterized by XRD, SEM, FTIR, and UV/Vis/NIR spectrophotometer. The photocatalytic property of pure Bi12SiO20 was also investigated by detecting the degradation rate of rhodamine B (RhB). The experimental conditions related to the preparation of pure phase bismuth silicate, such as the content of citric acid, calcination temperature schedule, and the molar ratio of Bi/Si were investigated. And when n(citric acid) = 13 mmol, n(Bi/Si) = 10, and heat preservation at 630 °C for 5 h, pure bismuth silicate powder can be successfully synthesized. And the degradation of RhB by Bi12SiO20 under visible light for 150 min can reach to 80%, which indicated that pure Bi12SiO20 is an excellent photocatalyst under the visible light. In addition, the capture experiments demonstrate that (Vo+) dominates in photocatalytic degradation.