Synthesis and characterizations of metastable Bi2SiO5 powders with a synergistic effect of adsorption and photocatalysis

Bi2SiO5 is a metastable phase compound and one of the important Bi-based Aurivillius phase oxide semiconductors. Pure Bi2SiO5 powders were synthesized successfully by Pechini sol-gel method. The samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, thermal analyzer, FTIR spectrometer, Raman spectrometer, fluorescence spectrophotometer and UV/Vis/NIR spectrophotometer. The mechanism of the reaction process was studied. The structure, the optical and photocatalytic properties of pure samples were investigated. The results show that citric acid, polyethylene glycol, solvents and calcination temperature have important effects on the reaction, and pure Bi2SiO5 can be obtained at 650 degrees C for 1 h. The as-prepared Bi2SiO5 has a typical Aurivillius-like structure and its bang gap energy is 3.5 eV. The results of degradation of Rhodamine B reveal that pure Bi2SiO5 powders prepared by Pechini sol-gel method possess a synergistic effect of adsorption and photocatalysis, which indicates that the Bi2SiO5 powders can be used as an efficient material for wastewater treatment.