Photocatalytic activity of WOx-TiO2 under visible light irradiation
Photocatalytic activity of WOx-TiO2 under visible light irradiation
复制标题
DOI：
10.1016/s1010-6030(01)00446-4
复制
发表时间：
2001-07-02
影响因子：
4.3
通讯作者：
Ge, WK
中科院分区：
文献类型：
--
作者：
Li, XZ;Li, FB;Ge, WK
为了将tio2基光催化剂的光吸收范围扩大到可见光范围，并消除光反应过程中激发电子/空穴的快速复合，采用溶胶-凝胶法制备了新型光催化剂WOx -TiO2粉体。通过一系列光降解水溶液中亚甲基蓝（MB）的实验，评价了WOx -TiO2催化剂的光氧化效率。采用x射线衍射（XRD）、紫外可见吸收光谱、x射线光电子发射光谱（XPS）、光致发光光谱（PL）、表面光电压光谱（SPS）和电子场诱导表面光电压光谱（EFISPS）对WO，-TiO2的光催化活性进行了表征。实验表明，在可见光照射下，WOx-TiO2成功地光降解了水溶液中的MB。结果表明，在本实验条件下，WOx-TiO2的最佳投加量为3%时，对MB的光降解率最高。证实WOx-TiO2可被可见光激发（E < 3.2 eV），并且由于TiO2中掺杂WO3的存在，WOx-TiO2中电子/空穴的复合率下降。其光活性由弱到强的顺序与PL强度和EFISPS强度由强到弱的顺序一致。(C) 2001 Elsevier Science B.V.版权所有
With an attempt to extend light absorption of the TiO2-based photocatalysts toward the visible light range and eliminate the rapid recombination of excited electrons/holes during photoreaction, new photocatalyst (WOx -TiO2) powder was prepared by a sol-gel method. The photooxidation efficiency of WOx -TiO2 catalyst was also evaluated by conducting a set of experiments to photodegrade methylene blue (MB) in aqueous solution. The photocatalytic activity of WO,-TiO2 was examined by X-ray diffraction (XRD), UV-VIS absorption spectra, X-ray photoelectron emission spectroscopy (XPS), photoluminescence spectra (PL), surface photovoltage spectra (SPS) and electron-field-induced surface photovoltage spectra (EFISPS). The experiments demonstrated that the MB in aqueous solution was successfully photodegraded using WOx-TiO2 under visible light irradiation. It was found that an optimal WO, dosage of 3% in WOx-TiO2 achieved the highest rate of MB photodegradation in this experimental condition. It has been confirmed that WOx-TiO2 could be excited by visible light (E < 3.2 eV) and the recombination rare of electrons/holes in WOx-TiO2 declined due to the existence of WO3 doped in TiO2. The order of its photoactivity from weak to strong had a good agreement with that of PL intensity and that of EFISPS intensity from strong to weak. (C) 2001 Elsevier Science B.V. All rights reserved.