摘要
基于纳米级耦合效应,采用溶胶-凝胶联合浸渍提拉法合成了Bi_2WO_6/TiO_2复合催化材料。利用XRD、SEM、UV-Vis、XPS和PL对Bi_2WO_6/TiO_2复合光催化剂进行了表征和分析,并对其可见光催化降解乙烯的光催化性能进行了评价。结果表明,Bi_2WO_6/TiO_2纳米复合材料比纯Bi_2WO_6、TiO_2具有更高的光催化活性。当Bi_2WO_6和TiO_2镀层比为3∶1时,乙烯的可见光催化降解效果最好,其降解率分别比TiO_2和纯Bi_2WO_6高5.4和2.4倍。纳米复合材料的光催化活性的提高主要是由于在Bi_2WO_6和TiO_2的接触界面形成了交错异质结。这改善了复合材料中晶粒在交界面处的晶格缺陷,提供了更多的活性位点,提高了光生电子空穴对的分离效率,并将光谱响应范围扩展到可见光区域,提升了光能的吸收和利用。
Based on the nanoscale coupling effect,Bi2WO6/TiO2 nanocomposites photocatalysts were synthesized by sol-dip-coating method.The obtained Bi2WO6/TiO2 photocatalyst was characterized and analyzed by XRD,SEM,UV-Vis,XPS,PL,respectively.And their photo-catalytic activities were evaluated for the degradation of ethylene under visible light irradiation.The result show that Bi2WO6/TiO2 nanocomposites have higher photocatalytic activity than TiO2 and pure Bi2WO6.When the coating ratio of Bi2WO6/TiO2 is 3∶1,the photocatalytic degradation of ethylene under visible light is the highest,which is 5.4 and 2.4 times higher than that of TiO2 and Bi2WO6,respectively.The improvement of the photocatalytic activity of the nanocomposite is mainly due to the formation of the staggered heterjunctions in the contact interface of TiO2 and Bi2WO6.This can refine the grain and produce lattice defects in the interface of the composite,which could provide more active sites.Therefore,the separation efficiency of the photogenerated electron-hole pair is improved,and the spectral response range is extended to the visible light region,thereby the absorption and utilization of light energy is improved.
作者
卢明剑
杨洲
赵文锋
李焱
LU Mingjian;YANG Zhou;ZHAO Wenfeng;LI Yan(College of Engineering,South China Agricultural University,Guangzhou 510642,China;College of Food,South China Agricultural University,Guangzhou 510642,China)
出处
《功能材料》
EI
CAS
CSCD
北大核心
2018年第7期7093-7098,7105,共7页
Journal of Functional Materials
基金
国家自然科学基金资助项目(51675189)
关键词
Bi2WO6
TIO2
可见光
光催化
Bi2 WO6
titanium oxide
visible light
photocatalytic degradation
