催化学报 ›› 2006, Vol. 27 ›› Issue (12): 1101-1106.

• 研究论文 • 上一篇    下一篇

氮掺杂TiO2/SiO2核壳型复合微球的制备及其可见光催化性能

黄浪欢,陈彩选,刘应亮   

  1. 暨南大学化学系; 暨南大学纳米化学研究所, 广东广州 510632
  • 收稿日期:2006-12-25 出版日期:2006-12-25 发布日期:2006-12-25

Preparation of Nitrogen-Doped TiO2/SiO2 Microspheres with Core-Shell Structure and Their Photocatalytic Activity under Visible Light

HUANG Langhuan, CHEN Caixuan, LIU Yingliang*   

  1. Chemistry Department, Jinan University; Institute of Nano-Chemistry, Jinan University, Guangzhou 510632, Guangdong, China
  • Received:2006-12-25 Online:2006-12-25 Published:2006-12-25

摘要: 以单分散性良好的SiO2微球为模板,以钛酸四丁酯为钛源,利用化学吸附和原位水解方法制备了TiO2/SiO2核壳结构复合微球,并在氨气气氛下进行了氮掺杂. 以罗丹明B水溶液的光催化降解为模型反应,评价了所制试样在可见光照射下的光催化活性,并借助透射电镜、高分辨透射电镜、 X射线衍射、紫外-可见漫反射光谱、红外光谱和X射线光电子能谱等测试手段对其结构、形貌和光谱性质进行了表征. 结果表明,氮掺杂TiO2/SiO2为核壳结构, TiO2包覆层厚约10 nm. 由于SiO2核与TiO2壳间形成了 Ti-O-Si 键, TiO2的热稳定性增强. 掺杂的氮形成了 Ti-O-N 键. 600 ℃下氮化1 h得到的试样的可见光活性最佳. 由于结合了SiO2核优良的吸附性能及氮掺杂TiO2壳的可见光响应性能,该复合微球在整体上表现出比P25更优的光催化活性.

关键词: 氮掺杂, 可见光, 二氧化钛, 二氧化硅, 核壳结构, 光催化

Abstract: TiO2/SiO2 microspheres with core-shell structure were synthesized by chemical adsorption and in situ hydrolysis using well-dispersed SiO2 microspheres as the template and tetrabutyl titanate as the precursor. The samples were calcined in a tube furnace under ammonia atmosphere at various temperatures to dope with nitrogen. The structure and morphology of the obtained samples were characterized by transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, ultraviolet-visible diffuse reflectance spectroscopy, infrared spectroscopy, and X-ray photoelectron spectroscopy. The photocatalytic activity was evaluated by the degradation of rhodamine B solution under visible light irradiation. TiO2/SiO2 was of core-shell structure, and the TiO2 shell was about 10 nm in thickness. The phase transition of TiO2 at high temperature was inhibited by the formation of the Ti-O-Si bond. TiO2/SiO2 was modified by N doping in the form of the Ti-O-N bond. The effects of calcination temperature on the photocatalytic activity were investigated. The highest activity was obtained with TiO2/SiO2 calcined at 600 ℃ for 1 h under ammonia atmosphere. The SiO2 core resulted in better adsorption property, and the N-doped TiO2 shell resulted in visible light sensitization. N-doped TiO2/SiO2 benefited from both of the effects.

Key words: nitrogen doping, visible light, titania, silica, core-shell structure, photocatalysis