Identification of active gold nanoclusters on iron oxide supports for CO oxidation
Identification of active gold nanoclusters on iron oxide supports for CO oxidation
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DOI：
10.1126/science.1159639
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发表时间：
2008-09-05
期刊：
影响因子：
56.9
通讯作者：
Hutchings, Graham J.
中科院分区：
文献类型：
--
作者：
Herzing, Andrew A.;Kiely, Christopher J.;Hutchings, Graham J.
吸附在金属氧化物上的金纳米晶体在氧化催化中具有特殊的性能，包括在环境温度下氧化一氧化碳，但在实际催化剂上存在的许多活性催化金物种中鉴定具有挑战性。我们使用像差校正扫描透射电子显微镜分析了几种氧化铁负载的催化剂样品，从活性低或无活性的到活性高的。一氧化碳氧化的高催化活性与双分子层簇的存在有关，这些双分子层簇的直径约为0.5纳米，只含有10个金原子。这些双层团簇的活性与先前使用模型催化剂系统所证明的一致。
Gold nanocrystals absorbed on metal oxides have exceptional properties in oxidation catalysis, including the oxidation of carbon monoxide at ambient temperatures, but the identification of the active catalytic gold species among the many present on real catalysts is challenging. We have used aberration- corrected scanning transmission electron microscopy to analyze several iron oxide- supported catalyst samples, ranging from those with little or no activity to others with high activities. High catalytic activity for carbon monoxide oxidation is correlated with the presence of bilayer clusters that are similar to 0.5 nanometer in diameter and contain only similar to 10 gold atoms. The activity of these bilayer clusters is consistent with that demonstrated previously with the use of model catalyst systems.