Development of Operando Polarization-Dependent Total Reflection Fluorescence X-ray Absorption Fine Structure Technique for Three-Dimensional Structure Determination of Active Metal Species on a Model Catalyst Surface under Working Conditions
Development of Operando Polarization-Dependent Total Reflection Fluorescence X-ray Absorption Fine Structure Technique for Three-Dimensional Structure Determination of Active Metal Species on a Model Catalyst Surface under Working Conditions
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工作条件下模型催化剂表面活性金属物质三维结构测定的操作偏振相关全反射荧光X射线吸收精细结构技术的发展
DOI：
10.1021/acs.jpcc.1c02913
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Satoru Takakusagi,
中科院分区：
文献类型：
--
作者：
Bang Lu;Daiki Kido;Yuta Sato;Haoran Xu;Wang-Jae Chun;Kiyotaka Asakura;Satoru Takakusagi,
开发了一种新颖的操作X射线吸收精细结构（XAFS）技术，我们将其称为操作偏振依赖性全反射荧光（PTRF）-XAFS技术，该技术可以提供催化反应过程中分散在明确的单晶表面上的活性金属物质的价态（XANES）和三维（3D）结构（EXAFS）信息。一种新型紧凑型真空室，称为 anoperandoPTRF-XAFS 池，其内部体积为 216 cm3，用于在反应气体（高达大气压）存在的情况下在高温（<800 K）下对沉积金属物质进行 PTRF-XAFS 测量。在 PTRF-XAFS 测量期间，可以使用四极杆质谱仪 (QMS) 同时进行池中的产物气体分析。开发的operandoPTRF-XAFS技术应用于CO氧化反应过程中的Pt/α-Al2O3(0001)模型催化剂。室温下 Pt 沉积后，在 α-Al2O3(0001) 表面上形成了有利于二十面体 Pt55 结构的 Pt 簇，而在 493 K 的 CO 氧化反应下，它们转化为更大的立方八面体簇 (Pt147)。根据同步 QMS 和 XAFS，493 K 下 CO 氧化活性的周转频率 (TOF) 估计为 0.06 s–1测量。因此，operandoPTRF-XAFS 能够确定明确氧化物表面上金属物质的 3D 结构与其催化活性之间的关系。
A noveloperandoX-ray absorption fine structure (XAFS) technique was developed that we have called theoperandopolarization-dependent total reflection fluorescence (PTRF)-XAFS technique, which can provide information on the valence state (XANES) and three-dimensional (3D) structure (EXAFS) of active metal species dispersed on a well-defined single-crystal surface during catalytic reactions. A new compact vacuum chamber, termed anoperandoPTRF-XAFS cell, was designed with an internal volume of 216 cm3for PTRF-XAFS measurements of deposited metal species at high temperatures (<800 K) in the presence of reactant gases (up to atmospheric pressure). Product gas analysis in the cell can be simultaneously conducted with a quadrupole mass spectrometer (QMS) during the PTRF-XAFS measurements. The developedoperandoPTRF-XAFS technique was applied to a Pt/α-Al2O3(0001) model catalyst during the CO oxidation reaction. Pt clusters that favor an icosahedral Pt55structure were formed on the α-Al2O3(0001) surface after Pt deposition at room temperature, while they were converted to larger cuboctahedral clusters (Pt147) under the CO oxidation reaction at 493 K. The turnover frequency (TOF) of the CO oxidation activity at 493 K was also estimated to be 0.06 s–1from simultaneous QMS and XAFS measurements. Thus,operandoPTRF-XAFS has enabled the relationship between the 3D structure of a metal species on a well-defined oxide surface and its catalytic activity to be determined.
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DOI：
--
发表时间：
2004
期刊：
Chem.Phys.Lett. 384
影响因子：
--
作者：
K.Ijima;Y.Koike;W.J.Chun;Y.Sato;Y.Tanizawa;T.Shido;Y.Iwasawa;M.Nomura;K.Asakura
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K.Asakura
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影响因子：
2.9
作者：
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H. Yashiro
影响因子：
3.6
作者：
Lei, Yu;Jelic, Jelena;Miller, Jeffrey
通讯作者：
Miller, Jeffrey
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影响因子：
2.5
作者：
W. Chun;Y. Tanizawa;T. Shido;Y. Iwasawa;M. Nomura;K. Asakura
通讯作者：
K. Asakura
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影响因子：
3.8
作者：
J. Bokhoven;C. Lamberti
通讯作者：
C. Lamberti