ZnO/AgNbO3光催化剂的表征及活性研究
收稿日期: 2009-12-07
修回日期: 2010-02-08
网络出版日期: 2010-08-25
基金资助
江苏省普通高校研究生科研创新计划(CX09B-210Z); 国家自然科学基金(20876071, 20676057, 20871061)
Characterization and Photocatalytic Activity of ZnO/AgNbO3
Received date: 2009-12-07
Revised date: 2010-02-08
Online published: 2010-08-25
采用浸渍法合成ZnO/AgNbO3异质结光催化环境净化材料. 利用X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电镜(SEM)、紫外漫反射(DRS)等分析方法对催化剂进行了表征. XRD分析结果表明, Zn的掺杂并未改变本体AgNbO3的晶型结构; 随着Zn掺杂量和热处理温度的提高, 异质结光催化剂体系中ZnO晶相结构逐渐出现;同时, XPS结果也说明Zn以ZnO的形式存在. DRS分析说明ZnO的引入有助于提高可见光区的吸收强度. 无论在可见光还是紫外光照射下, 光催化降解亚甲基蓝染料(MB)实验证明ZnO掺杂有利于提高AgNbO3的活性. 当Zn掺杂量为3 wt%, 热处理温度为300℃时, 紫外光照射3 h下MB降解率达到93.5%. 并对ZnO引入后光催化活性提高的机理进行了分析.
关键词: 光催化; ZnO/AgNbO3; 亚甲基蓝; 表征
舒火明, 谢吉民, 许 晖, 李华明, 徐远国, 顾 正 . ZnO/AgNbO3光催化剂的表征及活性研究[J]. 无机材料学报, 2010 , 25(9) : 935 -941 . DOI: 10.3724/SP.J.1077.2010.00935
ZnO/AgNbO3 hetero-junction photocatalysts were prepared by impregnation method. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscope (XPS), scan electron microscope (SEM) and UV-Vis diffusion reflectance spectra (DRS). The results indicated that Zn dopant did not change the crystal structures of AgNbO3. With increasing Zn content and calcination temperature, the ZnO phase formed in the ZnO/AgNO3. XPS analysis indicated that Zn2+ existed as ZnO. The DRS spectra showed that Zn dopant enhanced the ability of visible light absorption of the ZnO/AgNbO3 samples. The photocatalysts doping with ZnO exhibited the enhanced photocatalytic activities for degradation of methylene blue (MB) under visible light and UV light irradiation. The highest efficiency was obtained when the sample calcined at 300℃ with 3 wt% Zn content under UV light irradiation. The mechanism of improving photocatalytic activity was also discussed.
Key words: photocatalytic; ZnO/AgNbO3; methylene blue; characterization
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