Effect of tungsten oxide on ceria nanorods to support copper species as CO oxidation catalysts

• 作者: Yu'nan Li Lin Gan Rui Si
• 来源期刊: 稀土学报（英文版）
• 年，卷（期）: 2021,（1）
• 所属期刊栏目: RARE EARTH CATALYSIS
• 页码范围: 43-50
• 页数: 8页
• 语种: 英文

摘要

In this work,tungsten oxide with different concentrations (0,0.4 at％,2.0 at％ and 3.2 at％) was introduced to the ceria nanorods via a deposition-precipitation (DP) approach,and copper species of ca.10 at％ were sequentially anchored onto the modified ceria support by a similar DP route.The aim of the study was to investigate the effect of the amount of tungsten oxide (0,0.4 at％,2.0 at％,and 3.2 at％) modifier on the copper-ceria catalysts for CO oxidation reaction and shed light on the structure-activity relationship.By the aids of multiple characterization techniques including N2 adsorption,high-resolution transmission electron microscopy (HRTEM),powder X-ray diffraction (XRD),X-ray absorption fine structure (XAFS),and temperature-programmed reduction by hydrogen (H2-TPR) in combination with the catalytic performance for CO oxidation reaction,it is found that the copper-ceria samples maintain the crystal structure of the fluorite fcc CeO2 phase with the same nanorod-like morphology with the introduction of tungsten oxide,while the textural properties (the surface area,pore volume and pore size) of ceria support and copper-ceria catalysts are changed,and the oxidation states of copper and tungsten are kept the same as Cu2+ and W6+ before and after the reaction,but the introduction of tungsten oxide (WO3) significantly changes the metal-support interaction (transfer the CuOx clusters to Cu-[Ox]-Ce species),which delivers to impair the catalytic activity of copper-ceria catalysts for CO oxidation reaction.