催化学报

催化学报 ›› 2008, Vol. 29 ›› Issue (3): 269-274.

• 研究论文 • 上一篇    下一篇

La掺杂TiO2光催化剂的制备与表征

赵清华,全学军,谭怀琴,桑雪梅   

  1. 重庆工学院化学与生物工程学院化学工程系, 重庆 400050
  • 收稿日期:2008-03-25 出版日期:2008-03-25 发布日期:2012-03-01

Preparation and Characterization of La-Doped TiO2 Photocatalysts

ZHAO Qinghua, QUAN Xuejun*, TAN Huaiqin, SANG Xuemei   

  1. Department of Chemical Engineering, School of chemical and Biological Engineering, Chongqing Institute of Technology, Chongqing 400050, China
  • Received:2008-03-25 Online:2008-03-25 Published:2012-03-01

PDF

891

被引次数

146

摘要： 用共沉淀法和溶胶-凝胶法制备了La掺杂TiO2光催化剂(La3+-TiO2), 并以罗丹明B为模型反应物,进行了光催化降解实验. 结果发现,共沉淀法制备的La3+-TiO2具有较高的光催化活性,当掺La量为1.0%、于800 ℃煅烧2 h时获得的催化剂活性最佳. 用X射线衍射、N2吸附、扫描电镜和电子探针等手段测定了两种方法制备的典型样品的结构和粒度分布. 两种方法制备的催化剂都是含有锐钛矿和金红石型TiO2的混合晶体,但共沉淀法制备的催化剂具有较高的锐钛矿含量、较大的晶粒和大孔/介孔的多级孔结构,这是其具有较高光催化活性的主要原因.

关键词: 光催化剂, 掺镧, 二氧化钛, 共沉淀法, 溶胶-凝胶法

Abstract: Lanthanum-doped TiO2, photocatalysts La3+-TiO2, were prepared by coprecipitation and sol-gel methods. Rhodamine B was used as the reactant to evaluate the photocatalytic activity of the catalyst samples. The results showed that the La3+-TiO2 catalyst prepared by coprecipitation exhibited obviously higher photocatalytic activity. The optimum preparation conditions of coprecipitation were lanthanum ions doped of 1%, calcination temperature of 800 ℃, and calcination time of2 h. The best catalyst samples were characterized byX-raydiffraction, N2 adsorption-desorption measurement, scanning electron microscopy, and electron probe microanalyses. The two photocatalysts prepared by coprecipitation and sol-gel both had mixed crystal structure of anatase and rutile, and the anatase contents were 80% and 70%, respectively. The higher photocatalytic activity of the La3+-TiO2 catalyst prepared by coprecipitation was mainly attributed to its more regular structure of anatase, larger crystal size, and hierarchical macro/mesoporous structure.

Key words: photocatalyst, lanthanum doping, titanium dioxide, coprecipitation, sol-gel method