钯/二氧化锆催化剂上的一氧化碳氧化：载体供体位点的作用

CO Oxidation over Pd/ZrO₂ Catalysts: Role of Support's Donor Sites.

作者信息

Vedyagin Aleksey A, Volodin Alexander M, Kenzhin Roman M, Chesnokov Vladimir V, Mishakov Ilya V

机构信息

Boreskov Institute of Catalysis SB RAS, Novosibirsk 630090, Russian.

Institute of Natural Resources, National Research Tomsk Polytechnic University, Tomsk 634050, Russian.

出版信息

Molecules. 2016 Sep 27;21(10):1289. doi: 10.3390/molecules21101289.

DOI:10.3390/molecules21101289

PMID:27689972

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6274247/

Abstract

A series of supported Pd/ZrO₂ catalysts with Pd loading from 0.2 to 2 wt % was synthesized. The ZrO₂ material prepared by a similar technique was used as a reference sample. The samples have been characterized by means of transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR), testing reaction of ethane hydrogenolysis (HGE), N₂ adsorption, and electron paramagnetic resonance (EPR) spectroscopy. 1,3,5-trinitrobenzene was used as a probe molecule for the EPR spin probe method. The catalytic performance of samples was tested in the model reaction of CO oxidation. It was shown that the concentration of donor sites of support measured by EPR spin probe correlates with catalytic behavior during light-off tests. Low concentration of donor sites on a support's surface was found to be caused by the presence of the specific surface defects that are related to existence of coordinately unsaturated structures.

摘要

合成了一系列钯负载量为0.2至2 wt%的负载型Pd/ZrO₂催化剂。采用类似技术制备的ZrO₂材料用作参比样品。通过透射电子显微镜（TEM）、X射线衍射分析（XRD）、X射线光电子能谱（XPS）、程序升温还原（TPR）、乙烷氢解测试反应（HGE）、N₂吸附和电子顺磁共振（EPR）光谱对样品进行了表征。1,3,5-三硝基苯用作EPR自旋探针法的探针分子。在CO氧化模型反应中测试了样品的催化性能。结果表明，通过EPR自旋探针测量的载体供体位点浓度与起燃测试期间的催化行为相关。发现载体表面供体位点浓度低是由与配位不饱和结构的存在相关的特定表面缺陷引起的。