AgBr/Zn3(OH)2V2O7·2H2O可见光催化降解亚甲基蓝溶液

采用水热和沉淀两步合成法制备AgBr/Zn₃(OH)₂V₂O₇·2H₂O催化剂,研究其在可见光下降解亚甲基蓝溶液的性能,并考察催化剂用量、亚甲基蓝溶液初始浓度、pH值以及盐浓度对光催化性能的影响,评价AgBr/Zn₃(OH)₂V₂O₇·2H₂O催化剂的重复使用性能。结果表明,在前驱液pH为10、120 ℃水热10 h、Ag与Br物质的量比为0.20条件下制备的复合催化剂在可见光下反应120 min后,1.0 g·L^-1的催化剂对10 mg·L^-1的亚甲基蓝溶液脱色率达到85.2%。NaCl对亚甲基蓝的降解起抑制作用,Na₂SO₄对亚甲基蓝的降解起促进作用。催化剂重复使用4次后,光照120 min后的亚甲基蓝溶液脱色率可达66.4%。催化剂对不同初始浓度亚甲基蓝溶液的光催化降解符合一级动力学模型。

Photocatalytic degradation of methylene blue over AgBr/Zn3(OH)2V2O7·2H2O under visible light

AgBr/Zn₃(OH)₂V₂O₇·2H₂O catalyst was prepared by hydrothermal and precipitation two-step synthesis method and tested in degradation of methyl blue solution under visible light.Effects of catalyst amount,initial concentration of methyl blue solution,pH,and salt concentration on photocatalytic performance was investigated and reusability of AgBr/Zn₃(OH)₂V₂O₇·2H₂O catalysts was evaluated.The results showed that,after 120 min reaction under visable light,decolorization rate of 10 mg·L^-1 methylene blue solution reached 85.2% over 1.0 g·L^-1 composite catalyst prepared under conditions of pH 10,hydrothermal temperature of 120℃ for 10 h,and Ag/Br molar ratio of 0.20.NaCl inhibited degradation of methylene blue while Na₂SO₄ promoted degradation of methylene blue.After 4 times of repeated use of the catalyst,decoloration rate of methylene blue solution reached 66.4% after light irradiation for 120 min.The photocatalytic degradation of methylene blue solution with different initial concentrations over the catalyst met first-order kinetic model.