Room-Temperature CO Oxidation Catalyst: Low-Temperature Metal-Support Interaction between Platinum Nanoparticles and Nanosized Ceria
Room-Temperature CO Oxidation Catalyst: Low-Temperature Metal-Support Interaction between Platinum Nanoparticles and Nanosized Ceria
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DOI：
10.1021/acscatal.6b00677
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发表时间：
2016-09-01
期刊：
影响因子：
12.9
通讯作者：
Kaper, Helena
中科院分区：
文献类型：
--
作者：
Gatla, Suresh;Aubert, Daniel;Kaper, Helena
铂纳米颗粒分散在纳米氧化铈上，经氢气预处理后，在室温下对CO氧化具有活性。还原的催化剂的高角度环形暗场扫描透射电子显微镜（HAADF-STEM）分析显示了在电子束下1 nm尺寸的铂颗粒的扩散，这是二维强金属载体相互作用的特征。原位X射线吸收荧光光谱（XAFS）揭示了2.1埃的Pt-O距离，其显著长于PtO 2中的Pt-O距离（2.0埃）。这种延长的Pt-O距离可以与铂物种与氧化铈以低温活性物种载体相互作用的形式的相互作用有关。这些发现有助于对低温催化体系的一般理解。
Platinum nanoparticles dispersed on nanosized ceria are active for CO oxidation at room temperature after hydrogen pretreatment. High angular annular dark field scanning transmission electron microscopy (HAADF-STEM) analysis of the reduced catalyst shows spreading of the 1 nm sized platinum particles under the electron beam, characteristic for a two-dimensional strong metal support interaction. In situ X-ray absorption fluorescence spectroscopy (XAFS) reveals a Pt-O distance of 2.1 angstrom, which is significantly longer than the Pt-O distance in PtO2 (2.0 angstrom). This elongated Pt-O distance can be related to interaction of the platinum species with cerium oxide in the form of a low-temperature active species support interaction. These findings contribute to the general understanding of catalytic systems operating at low temperature.