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用液相沉淀法制备了钡掺杂钒酸铁(FeVO4)光催化剂。采用X射线衍射、扫描电子显微镜、能谱、比表面积、紫外-可见漫反射光谱和X射线光电子能谱对样品进行表征,并以甲基橙为模拟污染物对光催化性能进行测定。结果表明:Ba2+掺杂没有改变FeVO4晶型,部分Ba2+进入FeVO4晶格中引起晶格膨胀,晶胞体积增大。掺杂后表面形貌产生了较大变化,掺杂的钡生成新相BaV2O6附着在FeVO4晶体表面,起到表面修饰作用,但其比表面积基本无变化。掺杂Ba2+后其光吸收能力增强,禁带宽度减小。光催化脱色甲基橙溶液表明,适量Ba2+掺杂可提高FeVO4的光催化性能,在所进行的实验条件下,钒酸钡最佳掺杂量为12%(质量分数)时,掺杂后FeVO4对甲基橙溶液的脱色率较未掺杂前的提高31%左右。
Barium-doped iron-vanadate (FeVO4) photocatalysts were prepared by liquid-phase precipitation. The samples were characterized by X-ray diffraction, scanning electron microscopy, energy spectrum, specific surface area, UV-visible diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy. The photocatalytic activity of methyl orange as a simulated pollutant was determined. The results show that Ba2 + does not change the crystal form of FeVO4, some Ba2 + enters the FeVO4 lattice and causes lattice expansion, and the unit cell volume increases. After doping, the morphology of the surface was greatly changed. The new phase BaFe2O4 doped with barium was attached on the surface of FeVO4 crystal, which played the role of surface modification, but its specific surface area was almost unchanged. After Ba2 + doping, its light absorption ability is enhanced, the forbidden band width is reduced. Photocatalytic decolorization of methyl orange solution shows that the proper amount of Ba2 + doping can improve the photocatalytic activity of FeVO4. Under the experimental conditions, when the optimal doping amount of barium vanadate is 12% (mass fraction), the doped FeVO4 The decolorization rate of methyl orange solution than without doping before the increase of about 31%.