以离子液体([C4MIM]BF4)为模板剂，采用溶胶-凝胶法制备了介孔 TiO2和 Co掺杂的介孔 TiO2光催化剂。研究了Co掺杂对样品的比表面积、晶相、元素价态、吸光特性及可见光活性的影响。结果表明：所制备的Co/TiO2光催化剂为介孔结构的具有较大比表面积的锐钛矿相纳米颗粒； XPS分析表明： Co以Co2+取代Ti4+进入TiO2晶格形成杂质能级，降低了 TiO2带隙能，有效拓展了 TiO2的光响应范围。以亚甲基蓝水溶液为降解对象，在可见光(λ＞420 nm)下考察制备样品的光催化活性，结果表明：Co掺杂的TiO2具有可见光活性，且0.3%Co/TiO2的活性最高。
Co-doped mesoporous TiO2 photocatalysts were prepared by an ionic liquid 1-butyl-3-methylimida-zolium tetrafluoroborate ([C4MIM]BF4) modified Sol-Gel method. The effects of Co doping on the surface area, crystalline phase, chemical binding states and compositions, and absorbance of the Co-doped mesoporous TiO2 photocatalysts were studied by N2 adsorption-desorption measurements (BET), X-ray diffraction (XRD), X-ray photoelectron spec-troscopy (XPS), and UV-Vis diffuse reflectance absorption spectra (UV-Vis DRS). BET analysis showed that Co/TiO2 photocatalyst was mesoporous structure with large surface area. XRD patterns indicated that the Co-doped mesoporous TiO2 photocatalysts was anatase structure. XPS spectra indicated that the Co2+replaced Ti4+and entered into TiO2 lat-tice, which reduced the band gap of TiO2 and thereby extending the light response range to the visible region (UV-Vis spectra). Photocatalytic activity of the Co/TiO2 mesoporous photocatalysts was evaluated by photodegradation of me-thylene blue (MB) under visible light (λ>420 nm). Co-doped TiO2 exhibited obvious visible light activity for MB photodegradation, and 0.3%Co/TiO2 exhibited the highest photocatalytic activity.
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