催化学报

催化学报 ›› 2010, Vol. 31 ›› Issue (8): 1037-1043.DOI: 10.3724/SP.J.1088.2010.00442

• 研究论文 • 上一篇    下一篇

Mg-Al 类水滑石/二氧化钛异质复合纳米晶光催化氧化苯的性能

陈伟, 李旦振, 何顺辉, 邵宇, 黄艳, 付贤智   

  1. 福州大学光催化研究所, 福建福州 350002
  • 收稿日期:2010-04-26 出版日期:2010-08-30 发布日期:2013-12-26
  • 通讯作者: 李旦振

Photocatalytic Oxidation of Benzene on Nano-crystalline Mg-Al-HT/TiO2 Heterocompounds

CHEN Wei, LI Danzhen*, HE Shunhui, SHAO Yu, HUANG Yan, FU Xianzhi*   

  1. 福州大学光催化研究所, 福建福州 350002
  • Received:2010-04-26 Online:2010-08-30 Published:2013-12-26

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1254

被引次数

33

摘要： 采用过饱和沉淀法合成 n(Mg)/n(Al) = 2 的 Mg-Al 类水滑石化合物 (Mg-Al-HT), 再用水热法将它与钛胶复合, 制得 Mg-Al-HT/TiO2 异质复合光催化剂. 采用 X 射线粉末衍射、透射电子显微镜、场发射扫描电子显微镜、低温 N2 吸附-脱附、紫外-可见漫反射光谱和热重等技术对催化剂结构、成分和性质进行了表征. 结果表明, 在波长 365 nm 的紫外光照射降解苯的反应中, Mg-Al-HT/TiO2 异质复合光催化剂表现出优于单一的 TiO2 或 Mg-Al-HT 催化剂的光催化活性, 且稳定性更高; 同时讨论了该复合催化剂性能优异的原因. 另外, 运用电子顺磁共振技术检测到体系中存在羟基自由基等活性物种, 并据此提出了 Mg-Al-HT/TiO2 异质复合纳米晶催化剂光催化降解苯的反应机理.

关键词: 镁铝类水滑石, 二氧化钛, 苯, 异质复合物, 光催化

Abstract: Mg-Al hydrotalcite-like compounds (Mg-Al-HT) with Mg/Al molar ratio of 2 have been successfully synthesized by a supersaturated precipitation method and then mixed with a titania-sol to prepare nano-crystalline Mg-Al hydrotalcite-like compounds/TiO2 (Mg-Al-HT/TiO2) heterocompound photocatalysts by a hydrothermal method. The structure and components, Brunauer-Emmett-Teller spe-cific surface area, and photoresponse of the photocatalysts were characterized by powder X-ray diffraction, transmission electron micros-copy, field-emission scanning electron microscopy, N2 sorption, and ultraviolet-visible diffuse reflectance spectroscopy. The photocatalytic activity of the nano-crystalline Mg-Al-HT/TiO2 heterocompound photocatalysts for degradation of benzene was superior to that of single TiO2 or Mg-Al-HT under 365 nm light irradiation. The Mg-Al-HT/TiO2 heterocompound photocatalysts had higher stability. The electron paramagnetic resonance (EPR) technique was used to acquire the spin trapped-EPR spectra of the active species in the photocatalytic reac-tion. The possible photocatalytic reaction mechanism was also proposed.

Key words: magnesium-aluminium hydrotalcite-like compound, titanium dioxide, benzene, hetero compound, photocatalysis