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利用简单的溶剂热法制备LaFeO_3、La_(0.8)Sr_(0.2)FeO_(3-δ)以及非化学计量的La_(0.8)Sr_(0.2)FeO_(3-δ)(x=0.97,1.03)纳米颗粒。采用XRD、TEM、UV-Vis、XPS等手段对样品的形貌和结构进行表征,以孔雀石绿(MG)光降解为模型反应,在最大吸收波长下(616.9nm)考察材料的光催化性能。结果表明:Sr~(2+)的掺入减小了晶粒尺寸,致使晶体产生晶格畸变并形成氧空位V··O,抑制电子-空穴重组,增大量子效率;掺入Sr~(2+)并改变非化学计量,使得催化剂在可见光区域有较强的光吸收,比表面积增大,其中(La_(0.8)Sr_(0.2))1.03FeO_(3-δ)的比表面积最大(20.164 4m2/g),可见光降解效率也最高(83.8%)。Sr~(2+)掺杂及非化学计量LaFeO_3的可见光催化活性均高于纯LaFeO_3。
LaFeO_3, La_ (0.8) Sr_ (0.2) FeO_ (3-δ) and non-stoichiometric La_ (0.8) Sr_ (0.2) FeO_ (3-δ) (x = 0.97, 1.03) were prepared by a simple solvothermal method Granules. The morphology and structure of the samples were characterized by XRD, TEM, UV-Vis and XPS. The degradation of malachite green (MG) was modeled as a model reaction and the photocatalytic activity of the material was investigated at the maximum absorption wavelength (616.9 nm) . The results show that the incorporation of Sr ~ (2 +) decreases the grain size, resulting in crystal lattice distortion and oxygen vacancy V ·· O, suppressing electron-hole recombination and increasing quantum efficiency. (2 +) and changing the non-stoichiometry, the catalyst has stronger light absorption in the visible region and the specific surface area increases. The specific surface area of (La 0.8 Sr 0.2) 1.03 FeO 3- (3-δ) 20.164 4m2 / g), the highest visible light degradation efficiency (83.8%). The visible light catalytic activity of Sr ~ (2+) doping and non-stoichiometric LaFeO_3 are higher than pure LaFeO_3.