摘要
In this work, Bi2Ti2O7/TiO2 composites were synthesized and studied as potential visible-light-activated photocatalysts in the reduction of aqueous Cr（VI）. Bi2Ti2O7/TiO2 composites with tunable compositions were synthesized via a solvothermal-calcination two-step method, simply by changing the molar ratios of Bi（NO3）3·5H2O to tetrabutyl titanate in the reactants. The compositions, structures and optical properties of the as-synthesized Bi2Ti2O7/TiO2 composites were characterized by X-ray diffraction, field emission scanning electron microscopy and UV–vis diffuse reflectance spectra. The photocatalytic activity of the as-synthesized Bi2Ti2O7/TiO2 composites was tested in the reduction of aqueous Cr（VI）under visible-light（λ420 nm） irradiation, and compared with that of TiO2 nanoparticles. It was observed that the as-synthesized Bi2Ti2O7/TiO2 composites exhibited much higher photocatalytic activity than TiO2 nanoparticles, and the most efficient composite（300 mg） can achieve the complete reduction of Cr（VI） in 300 mL of 50 mg/L K2Cr2O7 aqueous solution under visible-light（λ420 nm）irradiation in 90 min.
In this work, Bi2Ti2O7/TiO2 composites were synthesized and studied as potential visible-light-activated photocatalysts in the reduction of aqueous Cr（VI）. Bi2Ti2O7/TiO2 composites with tunable compositions were synthesized via a solvothermal-calcination two-step method, simply by changing the molar ratios of Bi（NO3）3·5H2O to tetrabutyl titanate in the reactants. The compositions, structures and optical properties of the as-synthesized Bi2Ti2O7/TiO2 composites were characterized by X-ray diffraction, field emission scanning electron microscopy and UV–vis diffuse reflectance spectra. The photocatalytic activity of the as-synthesized Bi2Ti2O7/TiO2 composites was tested in the reduction of aqueous Cr（VI）under visible-light（λ420 nm） irradiation, and compared with that of TiO2 nanoparticles. It was observed that the as-synthesized Bi2Ti2O7/TiO2 composites exhibited much higher photocatalytic activity than TiO2 nanoparticles, and the most efficient composite（300 mg） can achieve the complete reduction of Cr（VI） in 300 mL of 50 mg/L K2Cr2O7 aqueous solution under visible-light（λ420 nm）irradiation in 90 min.
基金
funded by Natural Science Fund for Colleges and Universities in Jiangsu Province (No. 14KJB430022)
the Cultivating project of Xuzhou Institute of Technology (No. XKY2014103)
Innovative entrepreneurial training program of college student in Jiangsu province (No. xcx2015043)
The Opening Fund of Jiangsu Key Laboratory of Environmental Material and Environmental Engineering
