Novel Sieve-Like SnO2/TiO2 Nanotubes with Integrated Photoelectrocatalysis: Fabrication and Application for Efficient Toxicity Elimination of Nitrophenol Wastewater
Novel Sieve-Like SnO2/TiO2 Nanotubes with Integrated Photoelectrocatalysis: Fabrication and Application for Efficient Toxicity Elimination of Nitrophenol Wastewater
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DOI：
10.1021/jp205228h
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发表时间：
2011-09-22
影响因子：
3.7
通讯作者：
Li, Dongming
中科院分区：
文献类型：
--
作者：
Chai, Shouning;Zhao, Guohua;Li, Dongming
采用嵌段共聚物软模板法在垂直排列的二氧化钛纳米管（TiO 2 NTs）上组装了筛状大孔Sb掺杂SnO 2（Mp-SnO 2）薄膜，制备了具有优良光催化（PC）和电催化（EC）性能的新型电极。Mp-SnO 2的孔径范围为150 - 400 nm。大孔的构建可以增加比表面积，提供更多的活性中心。Mp-SnO 2/TiO 2纳米管的禁带宽度为2.93 eV，具有优异的光吸收和光电化学性能。在365 nm光照射下，Mp-SnO 2/TiO 2 NTs的光电转换效率为35.2%，是TiO 2 NTs的3.1倍。与传统的SnO 2/Ti电极相比，Mp-SnO 2/TiO 2 NTs具有更小的电化学阻抗、更大的电化学表面吸附体积和更低的反应活化能。研究了Mp-SnO 2/TiO 2纳米管集成光电催化氧化对硝基苯酚废水的性能。由于Mp-SnO 2/TiO 2 NTs的PC和EC性能之间具有显著的协同效应，有毒中间体易于焚烧，导致累积浓度相对较低。在4 h内，对硝基酚和TOC的去除率分别达到98%和91%，废水毒性消失。提出了PEC协同降解难降解污染物的机理。该研究为高浓度难降解废水的处理提供了一种独特的集成光电材料和一种有前途的技术。
A novel electrode with excellent photocatalytic (PC) and electrocatalytic (EC) performances was prepared by assembling sieve-like macroporous Sb-doped SnO2 (Mp-SnO2) film on vertically aligned TiO2 nanotubes (TiO2NTs) through a block copolymer soft-template method. The pore size of Mp-SnO2 ranges from 150 to 400 nm. The construction of the macropore can increase the specific surface area and provide more active sites. The band gap of the Mp-SnO2/TiO2NTs is 2.93 eV, and it presents outstanding light absorption and photoelectrochemical properties. Under the light irradiation of 365 nm, a high photoelectric conversion efficiency of 35.2% can be obtained on Mp-SnO2/TiO2NTs, 3.1 times higher than that on TiO2NTs. Compared with traditional SnO2/Ti electrodes, the Mp-SnO2/TiO2NTs displays smaller electrochemical impedance, a larger electrochemical surface absorption volume, and lower reaction activation energy. The integrated photoelectrocatalytic (PEC) oxidation of p-nitrophenol wastewater on Mp-SnO2/TiO2NTs is investigated. Because of the remarkable synergistic effect between PC and EC performances of Mp-SnO2/TiO2NTs, toxic intermediates are easily incinerated, resulting in relatively low accumulated concentrations. In 4 h, the p-nitrophenol and TOC removal reaches 98% and 91%, respectively, and the toxicity of the wastewater vanishes. The mechanism of synergistic PEC degradation of refractory pollutants is also proposed. This study provides a distinctive integrated photoelectric material and a promising technique for treatment of highly concentrated refractory wastewater effluent.