Fabrication of Weak-Room-Light-Driven TiO2-Based Catalysts through Adsorbed-Layer Nanoreactor Synthesis: Enhancing Catalytic Performance by Regulating Catalyst Structure

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• 作者：Ting Wang ; Yi-chen Zhu ; Zhi-yong Xu ; Li-guang Wu ; Ya-yu Wei ; Ti-nan Chen ; Bo-qiong Jiang
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：June 9, 2016
• 年：2016
• 卷：120
• 期：22
• 页码：12293-12304
• 全文大小：817K
• 年卷期：0
• ISSN：1932-7455

文摘

Aiming at photodegrading pollutants under room-light excitation, we fabricated TiO₂ composite catalysts driven by weak visible light through adsorbed-layer nanoreactor synthesis. Fe₂O₃ coupling and codoping by nonmetal elements were performed to enhance activity under irradiation of weak room light. By UV–visible diffuse reflectance spectra, high resolution transmission electron microscopy, X-ray diffraction, PL spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy analyses, the results showed that Fe₂O₃ coupling could extend the spectral response of the catalysts into the visible-light region. Two Fe₂O₃ coupling sequences exerted different effects on the microstructure of the catalysts. Fe₂O₃ strongly interacted with TiO₂ in the SiO₂–Fe₂O₃–TiO₂ catalysts, causing a more obvious visible-light response of SiO₂–Fe₂O₃–TiO₂ catalysts than SiO₂–TiO₂–Fe₂O₃ catalysts. Fe₂O₃ also significantly affected the crystallization of TiO₂ in SiO₂–Fe₂O₃–TiO₂ catalysts, thus introducing many shallow trapping sites for charge carriers. Nonmetal element doping, especially the codoping of N and B, could also enhance the visible-light response and the light absorbance of composite catalysts, as well as introduce impurities into the catalyst structure. Consequently, the activity under room-light irradiation was greatly improved. The degradation rate of the SiO₂–TiO₂–Fe₂O₃ catalyst codoped with N and B was approximately 45%, which was more than twice that of SiO₂–TiO₂–Fe₂O₃ catalyst.