化学学报 ›› 2012, Vol. 70 ›› Issue (22): 2353-2358.DOI: 10.6023/A12090636 上一篇    下一篇

研究论文

基于芭蕉叶分级结构的TiO2材料的制备及其吸附-光催化性能的研究

马欢a, 刘伟伟b, 朱苏文a, 樊芸杉c, 程备久a   

  1. a 安徽农业大学生命科学学院 合肥 230036;
    b 安徽农业大学工学院 合肥 230036;
    c 北京理工大学材料学院 北京 100081
  • 收稿日期:2012-09-07 出版日期:2012-11-28 发布日期:2012-10-29
  • 通讯作者: 程备久 E-mail:beijiucheng@ahau.edu.cn
  • 基金资助:
    项目受国家科技支撑计划重点项目(No. 2009BADA6B00)、国家自然科学基金(No. 31071423)和安徽农业大学校长青年基金重点项目(No. 2011ZD013)资助.

Biotemplated Hierarchical TiO2 Derived from Banana Leaf and Its Adsorption-Photocatalytic Performance

Ma Huana, Liu Weiweib, Zhu Suwena, Fan Yunshanc, Cheng Beijiua   

  1. a School of Life Science, Anhui Agricultural University, Hefei 230036;
    b School of Engineering, Anhui Agricultural University, Hefei 230036;
    c School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081
  • Received:2012-09-07 Online:2012-11-28 Published:2012-10-29
  • Supported by:
    Project supported by the National Science and Technology Pillar Program (No. 2009BADA6B00), the National Natural Science Foundation of China (No. 31071423) and the Major Research Plan of Anhui Agriculture University Principal Youth Fund (Grant 2011ZD013).

以芭蕉叶作为结构模板, 通过微波辐照-HCl耦合预处理、原位生长及变温去模板过程, 制备了具有分级多孔结构的TiO2光催化材料. 通过环境电子扫描显微镜(FESEM)、透射电镜(TEM)、 X射线衍射(XRD)及N2吸附-脱附表征. 结果表明: 芭蕉叶-TiO2材料不仅具有模板的维管束管状结构、大孔阵列及管壁内外宽度为100 nm左右的层状褶皱结构, 而且还具有典型的介孔结构, 平均孔径为13.03 nm, 材料比表面积为66.5 m2·g-1. 以染料亚甲基蓝(MB, C16H18ClN3S·3H2O)作为模型, 评价材料的吸附性能和光催化性能. 结果显示: 与DegussaP25及无模板的普通TiO2相比, 芭蕉叶-TiO2表现出较强的吸附性能和光催化活性; 对亚甲基蓝吸附率达30%, 为P25的4.3倍, 普通TiO2的15倍; 其光催化速率分别为P25和普通TiO2的1.5倍和4倍之多.

关键词: 分级结构, 二氧化钛, 芭蕉叶, 生物模板, 吸附-光催化

In recent years, there has been great interest in preparation of photocatalysts with hierarchical architectures and multifunctional characteristics, but it remains a great challenge for conventional synthetic methods. Nature provides an abundance of the biological materials with excellent properties and serves as a source of inspirations. In this work, banana leaves, for the first time, were applied as structure-directors to synthesize biomorphic TiO2 photocatalyst (banana-leaf TiO2), in order to improve the adsorption and photocatalytic performance. The biotemplate was pretreated by an effective microwave-assisted HCl pretreatment. Subsequently, the banana leaf-TiO2 composite formed based on the frameworks of original leaves by a simple in-situ growth using 5 vol% ethanol solution of tetrabutyl titanate as precursor. Finally, the banana-leaf TiO2, which faithfully inherits the hierarchical architectures of banana leaf, was obtained by calcination process at 350 ℃ to remove the organic templates and 500 ℃ to be crystallized. The as-prepared TiO2 samples were characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and nitrogen-adsorption measurement. The results show that the banana leaf-TiO2 prepared possesses both of macropores of vascular bundle with layers about 100 nm wide on the walls and typical mesopore structure with an average pore width of 13.03 nm and a high specific surface area of 66.5 m2·g-1. The adsorption and photocatalysis performance were evaluated using aqueous solutions of methylene blue (MB, C16H18ClN3S·3H2O) under Xe-lamp irradiation. The result indicates that the banana-leaf TiO2 exhibits much higher adsorption ability and photocatalytic activity than Degussa P25 and the common-TiO2 without any biotemplate. The adsorption capacity of biotemplated sample is 30%, which is 4.3 times of the P25 and 15 times of the common-TiO2. The photodecomposition of MB by the banana-leaf TiO2 reaches 100% over 75 min, comparative to 70% by P25 and 40% by the common-TiO2, and the photocatalytic rate of biotemplated sample (0.0326 min-1) is 1.5 times and 4 times the rate of P25 (0.0219 min-1) and common-TiO2 (0.0079 min-1), respectively.

Key words: hierarchical structure, titanium dioxide, banana leaf, biotemplate, adsorption-photocatalysis