TiO_2/活性炭负载型光催化剂的溶胶-凝胶法合成及表征  

Sol-Gel Preparation and Characterization of Activated Carbon Supported TiO_2 Photocatalyst

作　　者：刘守新[1] 陈曦[1] 

机构地区：[1]东北林业大学材料科学与工程学院,黑龙江哈尔滨150040

出　　处：《催化学报》2008年第1期19-24,共6页

基　　金：国家自然科学基金(30771692);教育部新世纪优秀人才资助计划;教育部博士点基金(20050225006)

摘　　要：以钛酸四丁酯为钛源,采用溶胶-凝胶法在多孔活性炭(AC)表面合成TiO2前驱体,在氮气保护下程序升温处理制得TiO2/AC负载型光催化剂.采用X射线衍射、漫反射光谱、傅里叶变换红外光谱、扫描电镜、能量色散谱和低温液氮吸附等对光催化剂晶相结构、光谱特征及表面结构进行了表征.结果表明,AC可提高TiO2分散性能,降低TiO2团聚体的尺寸,并抑制其由锐钛矿相向金红石相的转变.TiO2与AC接触界面处有Ti-O-C键生成.另外,AC的含量对TiO2的能阈结构和晶粒大小影响不大.苯酚溶液的光催化降解测试结果表明,AC负载可为TiO2提供高浓度反应环境,适宜量的负载可显著提高TiO2对有机稀溶液的光催化降解活性.对于50mg/L苯酚的光催化降解,AC的质量分数分别为5%,9%和11%时催化剂协同系数分别为1.1,1.5和1.3.循环使用7次后,AC含量为9%的催化剂对苯酚的降解率仍达95.84%.Activated carbon （AC）-supported TiO2 photocatalysts （TiO2/AC） were prepared by a sol-gel method from Ti（OBu）4. The photocatalysts were characterized by X-ray diffraction, diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopic analysis, and N2 adsorption isotherm. The results indicated that AC could improve the dispersion, decrease the aggregate size, and inhibit the phase transformation of TiO2 from anatase to futile. Ti-O-C bonds were formed between the AC bulk and TiO2. AC had no effect on the band-gap structure and crystalline size of TiO2. The photo- catalytic activity was investigated by phenol degradation. The results showed that AC could provide high reaction concentration for TiO2. TiO2/AC with a suitable AC content exhibited higher activity than naked TiO2 for low concentration phenol. Synergy coefficients observed for the catalyst with 5 %, 9 %, and 15 % AC were 1.1, 1.5, and 1.3, respectively. Phenol removal of 95.84 % was achieved even when the catalyst with 9 % AC was recycled seven times.

关 键 词：活性炭 二氧化钛 溶胶-凝胶 负载型光催化剂 苯酚 降解 

分 类 号：O643.36[理学—物理化学]