Preparation, Characterization And Photocatalytic Properties Of Metals Doped Bi₂O₃ And Bi₂XO₆（X=Mo、W）

Photodegradation has achieved consideration, ZnO and TiO2 photocatalyst have been studied by many researchers. Ultraviolet light can be used for the photocatalyst with wider band gap, which can occupy 5% in solar spectrum. Therefore, it is a predominating direction to develop visible light response photocatalyst. Metals doped Bi2O3-baed photocatst has widened the light absorption range and improved the photocatalytic activity in this paper. The main content was as following:(1) Preparation, characterization and study of bare Bi2O3. Different molar concentration of Bi2O3 were synthesied by co-precipitation method using Bi(NO3)3·5H2O as Bi source and NaOH as precipitation reagent, respectively. Also, XRD, SEM, Uv-vis and photocatalytic activity were texted to characterized the as-prepared samples. From the results we can know that all samples were monoclinic structure, and the morphology is incompletely same for different molar concentration. Compared to TiO2, red shift was achived and the absorption edge has been widen to visible light spectrum(λ>400 nm). In MO photocatalytic activity test, 0.4 mol/L sample exhibited the best activity under UV light irradiation. Meanwhile, activity of sample under visible light had been done.(2) Samples of Y, noble Ag and Mo element doping pure Bi2O3 were prepared using Bi(NO3)3·5H2O as Bi source, and Y(NO3)3, AgNO3 and Na2MoO4 as Ag and Mo source, respectively. Testing results show that chemical element doping can’t change the crystal structure of Bi2O3, which we can conclude that the ions had been entered into the Bi2O3 crystal lattice. Photocatalytic test results show that samples of Y, Ag and Mo doping Bi2O3 exhibited a better photocatalytic activity than pure Bi2O3. Photocatalytic mechanism of Ag doping Bi2O3 was proposed by the results.(3) Bi2MoO6 and Bi2MoO6/Bi2O3 sample were also prepared by different molar ratio of Bi/Mo and were characterized. Visible light response photocatalyst Bi2WO6 was prepared by molar ration of Bi:W=2:1 using hydrothermal and alcohol thermal method to explore effect of synthesis method on the photocatalytic activity of target product.(4) Meanwhile, new heterostructure YBiO3/Bi2O3 photocatast was prepared to further explore the role of metal Y in improving photocatalytic activity of Bi2O3. Results show that photocatalytic acitivty of YBiO3/Bi2O3 is better than bare Bi2O3.