Investigation of the Facet-Dependent Catalytic Performance of Fe2O3/CeO2 for the Selective Catalytic Reduction of NO with NH3

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• 作者：Jin Han ; Jittima Meeprasert ; Phornphimon Maitarad ; Supawadee Nammuangruk ; Liyi Shi ; Dengsong Zhang
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：January 28, 2016
• 年：2016
• 卷：120
• 期：3
• 页码：1523-1533
• 全文大小：827K
• ISSN：1932-7455

文摘

The facet-dependent catalytic performance of Fe₂O₃/CeO₂ catalysts for the selective catalytic reduction of NO with NH₃ (NH₃–SCR) has been investigated using combined experimental and density functional theory (DFT) methods. The structure and surface characteristics of the synthesized samples were characterized by XRD, XPS, TEM, ICP–AES, N₂ sorption isotherms, Raman spectra, photoluminescence spectra, H₂–TPR, NH₃–TPD and NO + O₂–TPD. It is found that the CeO₂ nanorods and Fe₂O₃/CeO₂ nanorods predominately exposed {110} and {100} facets rather than the stable {111} facets on CeO₂ nanopolyhedra and Fe₂O₃/CeO₂ nanopolyhedra. The influence of the micromorphologies and surface properties of CeO₂ supports on the NO conversion and N₂ selectivity has been compared. The Fe₂O₃/CeO₂ nanorods achieve higher catalytic activity than the Fe₂O₃/CeO₂ nanopolyhedra for NH₃–SCR of NO. The synergetic effect between CeO₂ supports and Fe₂O₃ species has been demonstrated. The insight into molecular facet dependence by the DFT method clearly showed that the Fe₂O₃/CeO₂ {110} catalyst is more reactive to NO and NH₃ gases than the Fe₂O₃/CeO₂ {111} and naked CeO₂ {110}, which agree well with the experimental results. As a result, the outstanding catalytic performance of Fe₂O₃/CeO₂ nanorods is attributed to the adsorbed surface oxygen, oxygen defects and atomic concentration of Fe which are associated with their exposed {110} and {100} facets of nanorods.