Platinum nanoparticles on Al2O3: Correlation between the particle size and activity in total methane oxidation
Platinum nanoparticles on Al2O3: Correlation between the particle size and activity in total methane oxidation
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DOI：
10.1016/j.jcat.2009.09.001
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发表时间：
2009-11-15
影响因子：
7.3
通讯作者：
Parmon, Valentin N.
中科院分区：
文献类型：
--
作者：
Beck, Irene E.;Bukhtiyarov, Valerii I.;Parmon, Valentin N.
酸处理过的γ-Al_2O_3负载的尺寸可控的铂纳米粒子在贫氧条件下的甲烷完全氧化中的催化活性被测试。铂颗粒平均尺寸为1.3~10 nm，粒度分布较窄(透射电子显微镜数据)。研究发现，所研究的反应具有很强的尺寸敏感性。催化剂比活性的尺寸依赖关系较窄且呈钟形，其中部分氧化铂催化剂的TOF值最大，平均粒径约为2 nm。观察到的强尺寸敏感性来自于催化活性纳米颗粒中甲烷氧化的表观活化能和/或铂的氧化态的尺寸依赖性。(C)2009 Elsevier Inc.保留所有权利。
Catalytic activity of the size-controlled platinum nanoparticles supported on the acid-pretreated gamma-alumina has been tested in complete methane oxidation under lean conditions. The mean sizes of platinum particles varied from 1.3 to 10 nm with the narrow size distribution (TEM data). It has been found that the reaction under study is strongly size sensitive. The size dependence of the specific catalytic activity is narrow and bell-shaped, with the maximum TOF value observed for the catalysts containing partially oxidized platinum with the mean particle sizes of about 2 nm. The observed strong size sensitivity is shown to originate from the size dependence of the apparent activation energy of the methane oxidation and/or the platinum oxidation state in the catalytically active nanoparticles. (C) 2009 Elsevier Inc. All rights reserved.