磁性BiVO_4可见光催化材料的制备及光催化性能  

Visible-Light-Driven Magnetic BiVO_4 Photocatalyst: Synthesis and Photocatalytic Performance

作　　者：刘坤杰[1] 常志东[1] 李文军[1] 车平[1] 周花蕾[1] 

机构地区：[1]北京科技大学化学与生物工程学院化学系,北京100083

出　　处：《无机化学学报》2011年第8期1465-1470,共6页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.20876015)资助项目

摘　　要：采用水相沉淀法,以Fe3O4粒子为核心,令BiVO4沉淀附着于其上,制备了一种更易于从溶液中分离的磁性BiVO4可见光催化材料,以XRD、SEM、UV-Vis DRS、低温氮吸附-脱附等对其进行了表征。结果表明制备的磁性BiVO4为单斜白钨矿型,颗粒呈片状,粒径比普通BiVO4有所增大,在可见光区的吸收更强,吸收边红移程度随Fe3O4含量增加而增大,但比表面积并没有明显改变。并以可见光(λ≥400 nm)为光源,以亚甲基蓝溶液模拟染料废水,考察了其可见光催化活性,发现与纯BiVO4相比,磁性BiVO4具有更为良好的催化性能。通过考察各催化剂的DRS图谱以及暗反应后亚甲基蓝的浓度,发现这种降解效率上的提高是禁带宽度(Eg)降低、可见光吸收增加和对亚甲基蓝吸附量增大综合作用所导致的。这种吸附量的提升与比表面积无关,本工作以等电点的影响来解释此原因。A visible-light-driven photocatalyst-magnetic BiVO 4-was synthesized by an aqueous deposition method and characterized by XRD,SEM,UV-Vis DRS and low temperature nitrogen adsorption-desorption.The results show that magnetic BiVO 4 photocatalysts have monoclinic scheelite structure and increase visible-light absorption.The BET specific surface area is a little lower than that of BiVO 4.The photocatalytic activity of magnetic BiVO 4 photocatalysts was investigated in methylene blue solution under visible-light irradiation.The photocatalytic activity of magnetic BiVO 4 photocatalysts is better than that of the pure one because of the reduction of E g,the enhancement of absorption in visible light region and increasement of adsorption of methylene blue.The increased adsorption of methylene blue is explained in terms of the lower isoelectric point of magnetic BiVO 4 than pure BiVO 4.

关 键 词：BIVO4 可见光催化剂 等电点 光催化 

分 类 号：O614.53[理学—无机化学] O614.511[理学—化学]