Photoelectrocatalytic activity of mesoporous TiO2 thin film electrodes
Photoelectrocatalytic activity of mesoporous TiO2 thin film electrodes
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DOI：
10.1016/j.apcata.2008.10.054
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发表时间：
2009-02
影响因子：
5.5
通讯作者：
Wee Yong Gan;Huijun Zhao;R. Amal
中科院分区：
文献类型：
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作者：
Wee Yong Gan;Huijun Zhao;R. Amal
建立了系列薄层光电催化体系，研究了蒸发诱导自组装法制备的介孔二氧化钛薄膜电极的光电催化活性与其结构特征之间的关系。以Pluronic F127为结构导向剂，通过控制涂层和热处理过程中的相对湿度和温度，改变了介孔薄膜电极的结构特征。测试了所制备的介孔二氧化钛薄膜电极的关键结构特征。对于介孔二氧化钛薄膜，可以在350℃的较低热处理温度下引入结晶度，而通过传统的溶胶-凝胶法制备的二氧化钛薄膜至少需要450℃的热处理温度才能引入相同程度的结晶度。以葡萄糖和琥珀酸为模型有机物分别代表弱吸附剂和强吸附剂，考察了关键结构参数对光电催化活性的影响。已报道的影响光催化活性的关键结构属性，如孔隙率、比表面积和结晶度，也对光电催化活性有重要影响，但影响方式不同。这是因为，对于光催化应用，催化剂的性能主要由单个催化剂颗粒的特性决定，而对于光电催化应用，催化剂的性能还取决于光催化剂层内的光电子传输过程，这反过来又强烈地依赖于诸如光催化剂颗粒的互连和与导电衬底的接触等属性。
A serial thin-layer photoelectrocatalysis system was developed to study the relationships between the photoelectrocatalytic activity and the structural characteristics of the mesoporous TiO2film electrodes prepared by an evaporation-induced self-assembly method. The structural characteristics of the mesoporous film electrodes were altered by using Pluronic F127 as the structural directing agent and by controlling the relative humidity and the temperature during coating and thermal treatment processes. Key structural characteristics of the resultant mesoporous TiO2thin film electrodes were measured. For the mesoporous TiO2film, the crystallinity can be introduced at a low thermal treatment temperature of 350°C while at lest 450°C thermal treatment temperature will be required to introduce the same degree of crystallinity to a TiO2film prepared via a conventional sol–gel process. The effect of key structural parameters on the photoelectrocatalytic activity was investigated using glucose and succinic acid as the model organic compounds to represent weak and strong adsorbents, respectively. The reported key structural properties, such as porosity, surface area and crystallinity, that affect the photocatalytic activity were found to also critically affect the photoelectrocatalytic activity but in a different manner. This is because, for a photocatalysis application, the performance of a catalyst is mainly determined by the characteristics of individual catalyst particles, while for a photoelectrocatalysis application the performance of a catalyst also depends on the photoelectron transport process within the photocatalyst layer this in turn relies strongly on attributes such as photocatalyst particles’ interconnectivity and the contact to the conducting substrate.