In Situ Studies on the Dissociation and Photocatalytic Reactions of CH3OH on TiO2 Thin Film by Sum Frequency Generation Vibrational Spectroscopy
In Situ Studies on the Dissociation and Photocatalytic Reactions of CH3OH on TiO2 Thin Film by Sum Frequency Generation Vibrational Spectroscopy
复制标题
和频振动光谱原位研究 CH3OH 在 TiO2 薄膜上的解离和光催化反应
DOI：
10.1021/jp512798f
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发表时间：
2015-05-07
影响因子：
3.7
通讯作者：
Ren, Zefeng
中科院分区：
文献类型：
--
作者：
Feng, Ran-ran;Liu, An-an;Ren, Zefeng
近年来，二氧化钛在有机污染物的光降解和废水处理中得到了广泛的应用。然而，对于TiO2光催化反应的机理，尤其是在真实环境条件下的光催化反应，目前还知之甚少。在本研究中，利用表面特有的和频产生振动光谱工具，原位研究了甲烷在二氧化钛薄膜上的解离和光氧化反应，作为有机化合物光氧化的模型体系。实验结果表明，O2与CH3OH混合可促进CH3OH解离生成CH3O，紫外光不仅能诱导CH3OH解离生成CH3O，而且还能产生较大的非共振。为了模拟有机物的光降解过程，在好氧和厌氧条件下研究了二氧化钛薄膜上甲氧基的去除。我们观察到了两种类型的甲氧基，在两种条件下都有光催化反应。
Titanium dioxide (TiO2) has been widely used in the photodegradation of organic contaminants and wastewater treatment in recent years. However, the mechanism of photocatalytic reaction on TiO2 surfaces is still poorly understood, especially for the reactions under real environmental conditions. In the present study, the sum frequency generation vibrational spectroscopy, a surface-specific tool, has been employed to in situ study the dissociation and photooxidation reaction of CH3OH on TiO2 thin film, which served as a model system of photooxidizing organic compounds. The experimental results show that mixing O2 with CH3OH promotes more CH3OH dissociation to produce CH3O, and UV light can not only induce CH3OH dissociation to CH3O but also generate large nonresonance. To mimic the photodegradation process of organics, removing methoxy on the TiO2 thin film has been investigated under both aerobic and anaerobic conditions. We have observed two types of methoxy, photocatalytically reactive under both conditi...