物理化学学报 >> 2011, Vol. 27 >> Issue (06): 1509-1515.doi: 10.3866/PKU.WHXB20110624

催化和表面科学 上一篇    下一篇

二氧化钛涂覆多壁碳纳米管的制备及可见光催化活性

丛野, 秦云, 李轩科, 董志军, 袁观明, 崔正威   

  1. 武汉科技大学化学工程与技术学院, 湖北省煤转化与新型炭材料重点实验室, 武汉 430081
  • 收稿日期:2011-01-14 修回日期:2011-03-24 发布日期:2011-05-31
  • 通讯作者: 李轩科 E-mail:xkli8524@sina.com
  • 基金资助:

    国家自然科学基金(20803054, 50972110)资助项目

Preparation and Visible Light Photocatalytic Activity of Titanium Dioxide Coated Multiwalled Carbon Nanotubes

CONG Ye, QIN Yun, LI Xuan-Ke, DONG Zhi-Jun, YUAN Guan-Ming, CUI Zheng-Wei   

  1. Hubei Key Laboratory of Coal Conversion and New Carbon Materials, College of Chemical Engineering and Technology, Wuhan University of Science and Technology, Wuhan 430081, P. R. China
  • Received:2011-01-14 Revised:2011-03-24 Published:2011-05-31
  • Contact: LI Xuan-Ke E-mail:xkli8524@sina.com
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20803054, 50972110).

摘要:

以多壁碳纳米管(MWCNTs)为反应性模板, 金属钛粉为钛源, 采用熔盐法制备碳化钛涂覆的MWCNTs中间体, 然后通过控制氧化制备二氧化钛涂覆的MWCNTs复合光催化剂. 考察了熔盐反应温度、MWCNTs和钛粉的摩尔比及氧化温度等对产物的结构和形貌的影响. 采用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)、透射电子显微镜(TEM)和X射线光电子能谱(XPS)等技术对其进行了系统的表征; 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了催化剂的可见光(λ>420 nm)催化活性. 结果表明: 所制备的催化剂基本保持了原始MWCNTs的纤维状形貌, 二氧化钛涂层在MWCNTs表面分布均匀, 并与MWCNTs之间结合紧密, 形成了Ti-O-C键. MWCNTs增强了污染物亚甲基蓝在催化剂表面的吸附, Ti-O-C键的形成使得在二氧化钛价带附近形成了杂质能级, 提高了对可见光的吸收和利用, 因此所制备的TiO2/MWCNTs复合光催化剂表现出较高的可见光催化活性.

关键词: 碳纳米管, 二氧化钛, 碳掺杂, 涂层, 光催化

Abstract:

Titanium dioxide coated multiwalled carbon nanotubes (MWCNTs) composite photocatalysts were prepared by the controllable oxidation of titanium carbide coated MWCNTs obtained by the molten salt method using MWCNTs as a reaction template and metal titanium powder as a titanium source. The effects of the molten salt reaction temperature, the molar ratio of MWCNTs to titanium powder, and the oxidation temperature on the structure and morphology of the products were investigated. The samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The photodegra- dation of a methylene blue (MB) solution was used to evaluate the photocatalytic activity of the catalyst under visible light irradiation (λ>420 nm). The results suggest that the TiO2 coated MWCNTs keep the similar fibred morphology with the pristine MWCNTs. Uniform and fine well-dispersed TiO2 coatings on the surface of MWCNTs closely contact with the MWCNTs support and Ti-O-C chemical bonds form between them. The prepared TiO2/MWCNTs photocatalyst shows higher visible light photocatalytic activity because the MWCNTs increase the adsorption of methylene blue on the photocatalyst and an impurity state is formed close to the valence band of titanium dioxide, which can enhance the absorption and utilization of solar energy.

Key words: Carbon nanotube, Titanium dioxide, Carbon doping, Coating, Photocatalysis

MSC2000: 

  • O643