Evidence for the Active Species Involved in the Photodegradation Process of Methyl Orange on TiO2
Evidence for the Active Species Involved in the Photodegradation Process of Methyl Orange on TiO2
复制标题
TiO2 上甲基橙光降解过程中涉及活性物质的证据
DOI：
10.1021/jp209661d
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发表时间：
2012-02-09
影响因子：
3.7
通讯作者：
Shao, Yu
中科院分区：
文献类型：
--
作者：
Li, Wenjuan;Li, Danzhen;Shao, Yu
采用多种技术检测了TiO 2光催化剂降解橙子（MO）过程中的空穴、电子、羟基自由基（（OH）-O-中心点）和超氧自由基（O-2（中心点-））等活性物种。采用不同类型的活性物种清除剂，结果表明，MO氧化主要是由O-2（中心点-），空穴和（OH）-O-中心点自由基的参与。采用液相色谱/质谱联用技术对降解产物进行了表征，分析了降解产物随光照时间的转化规律。结合氧化还原电位、溶解氧、电导率和pH值的测定，揭示了MO在活性物种作用下在TiO 2上的降解过程。这是首次引入电极原位跟踪降解过程，这些参数将有助于解释其他有机污染物的降解过程。
Active species such as holes, electrons, hydroxyl radicals ((OH)-O-center dot), and superoxide radicals (O-2(center dot-)) involved in the photodegradation process of methyl orange (MO) over TiO2 photocatalyst were detected by several techniques. Using different types of active species scavengers, the results showed that the MO oxidation was driven mainly by the participation of O-2(center dot-), holes and (OH)-O-center dot radicals. Characterized by the liquid chromatography/mass spectrometry, the transversion of the degradation products with the light irradiation time was first analyzed. Combined with the measurement of oxidation reduction potential, dissolved oxygen, conductivity, and pH values, the degradation process of MO on TiO2 under the effect of the active species was revealed. This was the first time that electrodes were introduced to track the degradation process in situ, and these parameters would be helpful to explain the degradation processes of other organic pollutants.