Photocatalytic Properties of Titanium Dioxide

二氧化钛的光催化性能

• 批准号: 9401562
• 负责人: Aaron Wold
• 金额: $ 36万
• 依托单位: Brown University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-07-15 至 1996-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9401562&HistoricalAwards=false
• 关键词: Photocatalytic; Properties; Titanium; Dioxide

Wold This research focusses on the investigation of the photocatalytic activity of titanium and related compounds toward the degradation of organic contaminants present in aqueous solutions at low concentrations. Previous studies have shown that the activity of titanium oxide is dependent on the method of preparation, and that the best samples are obtained from a volatile precursor. Furthermore, the formation of active surface states can be enhanced by the addition of a small quantity (~3%) of a transition metal oxide containing a high formal valence state metal, e.a. tungsten oxides or molybdenum oxides. This increase in active site formation has been related to an increase in Lewis acidity as evidenced by increased reactivity with n-butylamine. The proposed research will, therefore, be directed as follows: 1) attempts will be made to prepare titanium with a higher photocatalytic activity than the best titanium oxide samples studied to date; 2) a second group of oxides will also be prepared by the use of supercritical carbon dioxide and they involve two oxides which do not form a ternary phase in bulk form; and 3)the work will be extended to a family of compounds closely related to rutile in which three titanium ions are replaced by two pentavalent and one divalent ions. %%% The photocatalytic oxidation of organic compounds in an aqueous solution containing a suspension of titanium(IV) oxide is a comparatively new method for the removal of impurities from water. The photoactivating light required is sunlight or near UV. Many organic compounds have been shown to be oxidized to carbon dioxide by this method. It has potential application in the treatment of both waste and drinking water. Titanium oxide thin film coating on floating beads has potential to photocatalyze the oxidation of organic compounds floating on water, such as those typically resulting from an oil spill. This research focusses on the investigation of the photocatalytic activity of Titaniu m and related compounds toward the degradation of organic contaminants present in aqueous solutions at low concentrations.

本研究的重点是研究钛和相关化合物对低浓度水溶液中存在的有机污染物的降解的光催化活性。 以前的研究表明，氧化钛的活性取决于制备方法，最好的样品是从挥发性前体中获得的。 此外，活性表面态的形成可以通过添加少量（~3%）的 含有高形式价态金属的过渡金属氧化物，氧化钨或氧化钼。这种活性位点形成的增加与刘易斯酸度的增加有关，这通过与正丁胺的反应性增加来证明。 因此，所提出的研究方向如下：1）将尝试制备具有比迄今为止所研究的最好的二氧化钛样品更高的光催化活性的钛; 2）第二组氧化物也将通过使用超临界二氧化碳来制备，它们涉及两种在本体形式下不形成三元相的氧化物;以及3）工作将扩展到与金红石密切相关的化合物家族，其中三个钛离子被两个五价离子和一个二价离子取代。 %%% 在含有氧化钛（IV）悬浮液的水溶液中光催化氧化有机化合物是从水中去除杂质的相对较新的方法。所需的光活化光是阳光或近紫外线。 许多有机化合物已被证明可以用这种方法氧化成二氧化碳。它在废水和饮用水的处理中具有潜在的应用。涂覆在漂珠上的氧化钛薄膜具有光催化氧化漂浮在水面上的有机化合物的潜力，例如通常由石油泄漏产生的有机化合物。本研究的重点是研究钛及其相关化合物对低浓度水溶液中有机污染物的光催化降解活性。