盐酸溶液处理钒酸铋增强可见光催化活性及其机理

[Article]

物理化学学报(Wuli Huaxue Xuebao )

Acta Phys.-Chim.Sin.2012,28(12),2917-2923

December Received:July 19,2012;Revised:September 3,2012;Published on Web:September 3,2012∗

Corresponding author.Email:long_mc@;Tel:+86-21-54747354.

The project was supported by the National Natural Science Foundation of China (20907031).国家自然科学基金(20907031)资助项目

ⒸEditorial office of Acta Physico-Chimica Sinica

doi:10.3866/PKU.WHXB 201209032

盐酸溶液处理钒酸铋增强可见光催化活性及其机理

龙明策*

万

磊

曾

曾

刘伊依

陈渊源

(上海交通大学环境科学与工程学院,上海200240)

摘要:

采用盐酸水溶液处理BiVO 4的方法获得增强的光催化活性.在0.1mol ·L -1酸溶液中浸渍反应6h,

BiVO 4的可见光催化降解苯酚的活性提高了3.5倍.采用X 射线衍射(XRD),扫描电镜(TEM)和漫反射光谱(DRS)等表征手段研究处理后样品的晶相组成和表面形貌,结合不同酸和氯化物处理的对照实验,结果表明,在H +和Cl -的协同作用下,BiVO 4表面部分溶出并以BiOCl 沉积,形成了表面具有凹陷沟壑的BiVO 4颗粒与片状结构BiOCl 的复合物.采用悬浮液光电压法测定BiOCl 平带电位,通过BiVO 4和BiOCl 的能带分析及其混合颗粒的光催化活性测试,确证二者间不存在颗粒间电子转移效应.增强的光催化活性主要归因于BiVO 4表面形成了有助于光生电荷迁移的凹凸不平结构.这种表面处理方法有望成为一种增强半导体化合物光催化活性的有效途径.关键词:

光催化;BiVO 4;BiOCl;

异质结;表面纳米结构;可见光活性;苯酚降解

中图分类号:

O643

Enhanced Visible Light Activity of BiVO 4by Treating in

HCl Aqueous Solution and Its Mechanism

LONG Ming-Ce *

WAN Lei

ZENG Ceng

LIU Yi-Yi

CHEN Yuan-Yuan

(School of Environmental Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,P .R.China )Abstract:Enhanced photocatalytic activity of BiVO 4has been achieved by immersing in HCl aqueous solution.After treated for 6h in 0.1mol ·L -1HCl solution,the visible light activity of BiVO 4for phenol degradation increased by 3.5times.X-ray diffraction (XRD),scanning electron microscopy (SEM),and diffuse reflectance spectroscopy (DRS)were carried out to analyze the crystal components and surface morphology of the treated parison of samples treated in different acids and chlorides indicated that with the appropriate concentrations of H +and Cl -ions,BiVO 4partially dissolved,was deposited as BiOCl,and finally a composite of flaked BiOCl and micro-particles of BiVO 4with pits formed over the surface.The flatband potential of BiOCl was measured by a slurry method.According to the results of energy band analyses and photocatalytic activity tests of mixed BiVO 4and BiOCl particles,there is no interparticle electron transfer effect between them.Therefore,the mechanism of the enhanced photocatalytic performance of the treated BiVO 4can be attributed to the unevenness of the surface,which can facilitate photogenerated charge separation.This type of surface treatment method could be developed into an effective method for preparing photocatalysts with enhanced photocatalytic performance.Key Words:Photocatalysis;

Bismuth vanadate;

Bismuth oxychloride;Heterojunction;Surface

nanostructure;

Visible light activity;Phenol degradation

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