Fe_2O_3/Bi_2WO_6对微囊藻毒素的光催化降解研究

Photocatalytic Degradation Microcystin-LR by Fe_2O_3/Bi_2WO_6 under Visible Light

通过水热法制得可见光响应的Fe_2O_3/Bi_2WO_6复合光催化剂,利用X射线衍射(XRD)、扫描电镜(SEM)、紫外-可见漫反射(UV-Vis DRS)和分子荧光光谱(PL)进行表征。结果显示样品为花状超结构,Bi_2WO_6与Fe_2O_3复合后拓宽了可见光吸收范围,同时有效抑制了光生电子和空穴的结合几率。利用单因素实验考察了可见光照射下降解微囊藻毒素(MC-LR)的影响因素。结果表明,在Fe_2O_3/Bi_2WO_6催化剂投加量为0.05 g,pH值为3.7,MC-LR初始质量浓度为1 mg/L时降解速率最高,反应60 min内准一级动力学常数达到0.031 min^(-1)。

Visible light response Fe2O3/Bi2WO6 composites were prepared using hydrothermal method.The prepared catalysts were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),UV-vis diffuse reflectance spectroscopy(UV-Vis DRS)and photoluminescence(PL).The result show that the sample is flower-like superstructure,and the composite of Bi2WO6 and Fe2O3 broadens the visible light absorption range and effectively inhibits the recombination probability of photogenerated electrons and holes.Single factor experiments were used to investigate the factors affecting the degradation of MC-LR under visible light irradiation.The result show that the highest degradation rate of MC-LR was 0.031 min-1 when the catalyst dosage was 0.05 g,pH value was 3.7 and initial MC-LR concentration was 1mg/L.