Enhanced photocatalytic degradation and selective removal of nitrophenols by using surface molecular imprinted Titania
Enhanced photocatalytic degradation and selective removal of nitrophenols by using surface molecular imprinted Titania
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使用表面分子印迹二氧化钛增强光催化降解和选择性去除硝基酚
DOI：
10.1021/es071788p
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发表时间：
2008-03-01
影响因子：
11.4
通讯作者：
Tang, Heqing
中科院分区：
文献类型：
--
作者：
Shen, Xiantao;Zhu, Lihua;Tang, Heqing
二氧化钛（TiO 2）光催化剂的选择性差，不利于光催化去除污染沃茨中毒性较强的低浓度有机污染物。一种新的策略是通过在TiO 2表面涂覆一层分子印迹聚合物（MIP）来提高这种选择性，这提供了对模板分子的分子识别能力。以2-硝基苯酚和4-硝基苯酚为目标污染物，采用表面分子印迹法制备了MIP包覆的TiO 2光催化剂，并观察到其对目标污染物具有较高的光降解活性和选择性。在双酚A存在下（50 mg L ~（-1））作为非目标污染物时，目标2-硝基苯酚和4-硝基苯酚的光降解表观速率常数（1.8 mg L-1）相对于相应MIP涂覆的TiO 2的吸附速率分别为10.73 x 10（-3）和7.06 x 10（-3）min（-1），分别是纯TiO_2的2.46和4.61倍（4.36 × 10 ~（-3）min ~（-1）和1.53 × 10 ~（-3）min ~（-1））。增强的光催化选择性增加时，目标的浓度降低和/或当目标和非目标分子之间的化学结构和分子大小的差异增加。提高的选择性主要归因于目标分子和足迹聚合物之间通过官能团（-OH和-NO2）的特殊相互作用。
Poor selectivity of titania (TiO2) photocatalysis is unfavorable to photocatalytic removal of highly toxic low-level organic pollutants in polluted waters in the presence of other less toxic high-level pollutants. A new strategy of increasing this selectivity is the surface modification of TiO2 via coating a thin layer of molecular imprinted polymer (MIP), which provides molecular recognition ability toward the template molecules. By using 2-nitrophenol and 4-nitrophenol as target pollutants, MIP-coated TiO2 photocatalysts were prepared via surface molecular imprinting and were observed to have high activity and selectivity toward the photodegradation of the targets. In the presence of bisphenol A (50 mg L-1) as a nontarget pollutant, the apparent rate constant for the photodegradation of the target 2-nitrophenol and 4-nitrophenol (1.8 mg L-1) over the corresponding MIP-coated TiO2 was 10.73 x 10(-3) and 7.06 x 10(-3) min(-1), being 2.46 and 4.61 times of that (4.36 x 10(-3) and 1.53 x 10(-3) min(-1)) over neat TiO2, respectively. The enhanced photocatalytic selectivity was increased when the concentration of the target was decreased and/or when the difference in both the chemical structure and molecule size between the target and nontarget molecules was increased. The increased selectivity was mainly attributed to the special interaction between the target molecules and the footprints polymer via the functional groups (-OH and -NO2).