Co^(2＋)离子掺杂对TiO_2结构与光催化活性的影响  

Effects of Doping Co^(2+)Ion on the Structures and Photocatalytic Activity of TiO_2

作　　者：陈晴空[1] 吉芳英[1] 关伟[2] 晏鹏[1] 刘亭役[1] 徐璇[1] 

机构地区：[1]重庆大学 三峡库区生态环境教育部重点实验室,重庆400045 [2]重庆大学三峡库区生态环境教育部重点实验室,重庆400045

出　　处：《四川大学学报（工程科学版）》2013年第5期192-198,共7页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(51108483);中央高校基本科研业务费资金项目(CDJXS12210002);教育部科技创新工程重大项目培育资金项目(708071);重庆市自然科学基金资金项目(cstcjjA20002)

摘　　要：采用溶胶-凝胶法制备Co2+掺杂的TiO2纳米粉末,以苯酚为目标污染物研究了Co-TiO2在不同的光源(紫外、可见)下的光催化活性,并利用XRD、EFSEM、UV-DRS和XPS等手段分析Co-TiO2结构与光催化活性的关系。结果表明,一部分Co2+离子成功进入TiO2晶格,有助于金红石相向锐钛矿相转变;另一部分Co2+离子在催化剂表面生成Co3O4,可与TiO2形成p-n异质结。2种结构变化均增强了光催化活性,且催化剂光谱吸收范围拓展至可见光区域。当Co2+掺杂量为1.0%,焙烧温度为773 K时,Co-TiO2比表面积约为28.4 m2/g,锐钛矿含量达到70.6%,光催化活性最好。2 h内,在紫外和可见光下,Co-TiO2对苯酚的降解率分别为97.7%和52.3%,均优于纯TiO2。The Co-doped TiO2nano-powders were prepared by the sol-gel method,and their photocatalytic activities were measured by the degradation of phenol under different light resources（ UV and visible）. The structures of the powders were also studied through XRD,EFSEM,UV-DRS,and XPS,and the relationship between their structures and photocatalytic activities was analyzed. The results showed that a part of Co2＋ ions have doped into TiO2 lattice successfully and can promote the phase transformation from rutile to anatase,and the others have formed Co3O4 and loaded on the surface of the powder. The p- n junction is probable to be formed between Co3O4 and TiO2. These two changes of the structures enhance the photocatalitic activity of the catalyst obviously and the photon excited wavelength of the Co-TiO2 powder is broadened to visible light region. When the Co2＋doped concentration is 1. 0% and the calcination temperature is 773 K,the content of anatase phase in Co-TiO2 reaches 70. 6%,and the BET surface area is 28. 4 m2/ g,which represented the best catalytic activity in all samples. The degradation efficiency of phenol in 2 h is 97. 7% under UV and 52. 3%under visible light irradiation,respectively.

关 键 词：二氧化钛 掺杂 光催化 降解 

分 类 号：X703.1[环境科学与工程—环境工程]