催化学报

催化学报 ›› 2011, Vol. 32 ›› Issue (3): 508-512.DOI: 10.3724/SP.J.1088.2011.01121

• 研究论文 • 上一篇    下一篇

以尿素为氮源制备氮改性二氧化钛及其改性机理

黄涛, 张国亮, 王玲, 刘良军, 孙茜萍   

  1. 浙江工业大学生物与环境工程学院, 浙江杭州 310014
  • 收稿日期:2010-11-23 修回日期:2011-01-05 出版日期:2011-03-04 发布日期:2014-08-01

Preparation of Nitrogen-Modified Titania with Urea as Nitrogen Source and Its Modification Mechanism

HUANG Tao, ZHANG Guoliang*, WANG Ling, LIU Liangjun, SUN Xiping   

  1. College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
  • Received:2010-11-23 Revised:2011-01-05 Online:2011-03-04 Published:2014-08-01

PDF

1267

被引次数

42

摘要： 以钛酸丁酯为前驱体, 以尿素为氮源, 采用改进溶胶-凝胶法制备了不同 N 含量的改性 TiO2 光催化剂 (N-TiO2 ). 以重铬酸钾为目标污染物, 以甲酸为空穴捕获剂, 评价了可见光下该催化剂的催化还原活性. 结果表明, N-TiO2 催化剂活性明显高于未改性催化剂, 当催化剂中 N/Ti 摩尔比为 10%、焙烧温度为 400 oC 时, 其光催化还原活性最高. X 射线衍射、X 射线光电子能谱、傅里叶变换红外光谱和紫外可见漫反射吸收光谱等表征结果显示, 于 400 oC 焙烧时尿素分解生成了可起光敏化作用的氰尿酰胺. 这可能是相应 N-TiO2 样品具有较高可见光活性的原因.

关键词: 氮改性, 尿素, 二氧化钛, 溶胶凝胶法, 氰尿酰胺, 重铬酸钾

Abstract: A nitrogen-modified TiO2 (N-TiO2) catalyst with different nitrogen content was prepared by a modified sol-gel method, using tetrabutyl titanate as the precursor and urea as the nitrogen source. The catalyst samples were used in the photocatalytic reduction of Cr(Ⅵ) under visible light, using formic acid as a hole scavenger to enhance the photocatalytic reduction reaction. The results demonstrated that the N-TiO2 catalyst had higher photocatalytic activity than bare TiO2, and the N-TiO2 sample with 10% (molar ratio) nitrogen calcined at 400 oC held the highest photocatalytic efficiency. The N-TiO2 samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and ultraviolet visible diffuse reflectance spectroscopy. The results showed that the higher photocatalytic activity of the N-TiO2 sample calcined at 400 oC was mostly attributed to the melon condensation products, which acted as visible-light sensitizers.

Key words: nitrogen-modification, urea, titania, sol-gel method, melon, potassium dichromate