Quantitative analysis of superoxide ion and hydrogen peroxide produced from molecular oxygen on photoirradiated TiO2 particles
Quantitative analysis of superoxide ion and hydrogen peroxide produced from molecular oxygen on photoirradiated TiO2 particles
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DOI：
10.1016/j.jcat.2004.04.001
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发表时间：
2004-07-01
影响因子：
7.3
通讯作者：
Matsumura, M
中科院分区：
文献类型：
--
作者：
Goto, H;Hanada, Y;Matsumura, M
分子氧的还原是在二氧化钛颗粒上氧化进行的大多数光催化反应的逆反应。我们定量分析了在含有正空穴清除剂2-丙醇的水溶液中，由氧还原产生过氧化氢和超氧阴离子。过氧化氢和超氧离子的产生率分别用碘化物和四氮唑氮蓝比色法测定。此外，监测2-丙醇氧化成丙酮。基于这些生产率的比较，得出结论，当使用主要由锐钛矿型颗粒组成的TiO 2粉末时，来自氧的主要产物是过氧化氢，而当使用主要由金红石型颗粒组成的TiO 2粉末时，主要产物是超氧离子。这些粉末之间的光催化活性的差异可以归因于这些粉末上的氧的还原路径之间的差异。还发现由分子氧产生的超氧离子自发地与2-丙醇反应，生成丙酮和过氧化氢。(C)2004年爱思唯尔公司All rights reserved.
The reduction of molecular oxygen is the counter reaction of most photocatalytic reactions proceeding oxidatively on titanium dioxide particles. We have quantitatively analyzed the reductive production of hydrogen peroxide and superoxide ion from oxygen in an aqueous solution containing 2-propanol as the scavenger of positive holes. The rates for the production of hydrogen peroxide and superoxide ion were determined by colorimetry using iodide and nitroblue tetrazolium, respectively. In addition, the oxidation of 2-propanol to acetone was monitored. Based on a comparison of these production rates, it was concluded that the main product from oxygen is hydrogen peroxide when TiO2 powder consisting mainly of anatase-form particles is used, whereas the main product is superoxide ion when TiO2 powder consisting mainly of rutile-form particles is used. The difference in the photocatalytic activity between these powders can be attributed to the difference between the reduction paths of oxygen on these powders. It was also found that the superoxide ion generated from molecular oxygen spontaneously reacts with 2-propanol to produce acetone and hydrogen peroxide. (C) 2004 Elsevier Inc. All rights reserved.