CeO₂ nanorods-supported transition metal catalysts for CO oxidation

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• 作者：Samantha A. Mock ; Shannon E. Sharp ; Thomas R. Stoner ; Michael J. Radetic ; Elizabeth T. Zell ; Ruigang Wang ; ^{rwang01@ysu.edu" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Heterogeneous catalysis ; Electron microscopy ; Hydrothermal method
• 刊名：Journal of Colloid and Interface Science
• 出版年：2016
• 出版时间：15 March 2016
• 年：2016
• 卷：466
• 期：Complete
• 页码：261-267
• 全文大小：2641 K

文摘

A catalytically active oxide support in combination with metal catalysts is required in order to achieve better low temperature activity and selectivity. Here, we report that CeO₂ nanorods with a superior surface oxygen release/storage capability were used as an active support of transition metal (TM) catalysts (Mn, Fe, Co, Ni, Cu) for CO oxidation reaction. The as-prepared CeO₂ nanorods supported 10 wt% TM catalysts were highly active for CO oxidation at low temperature, except for the Fe sample. It is found that the 10%Cu–CeO₂ catalyst performed best, and it provided a lower light-off temperature with T50 (50% conversion) at 75 °C and T100 (100% conversion) of CO to CO₂ at 194 °C. The atomic level surface structure of CeO₂ nanorods was investigated in order to understand the improved low temperature catalytic activity. The richness of surface roughness and various defects (voids, lattice distortion, bending, steps, twinning) on CeO₂ nanorods could facilitate oxygen release and storage. According to XRD and Raman analysis, copper species migrate into the bulk CeO₂ nanorods to a greater degree. Since CO adsorbed over the surface of the catalyst/support is detrimental to its catalytic activity, the surface defects on the CeO₂ nanorods and CeO₂-TM interactions were critical to the enhanced activity.