First-Principles Analysis of Structure Sensitivity in NO Oxidation on Pt
First-Principles Analysis of Structure Sensitivity in NO Oxidation on Pt
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DOI：
10.1021/cs501783q
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发表时间：
2015-01
期刊：
影响因子：
12.9
通讯作者：
J. M. Bray;W. Schneider
中科院分区：
文献类型：
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作者：
J. M. Bray;W. Schneider
铂催化NO在铂(111)和铂(321)上的氧化反应动力学从第一性原理出发，采用覆盖感知的“反应中心”动力学模型进行了定量。用密度泛函理论(DFT)参数化团簇展开法预测了氧的覆盖率和氧解离位的可用性随反应条件的变化。用密度泛函理论计算得到了O2在铂(321)面上的Bronsted-Evans-Polanyi关系。对可用的位置及其相应的速率进行系综平均，得到总的反应速率。预测的表观活化能和速率级数与在单晶催化剂上的实验观测结果一致，并且最强烈地取决于氧吸附的覆盖度而不是氧解离中心的统计可用性。在实验观察的范围内，两个表面上的速率和速率导数是相似的，并且预测在这个范围之外会有更大的差异。
The kinetics of Pt-catalyzed NO oxidation on both Pt(111) and Pt(321) are quantified from first-principles using a coverage-aware “reaction site” kinetic model. Density functional theory (DFT)-parametrized cluster expansions are used to predict oxygen coverages and availability of O2 dissociation sites as a function of reaction conditions. DFT calculations are used to parametrize a Bronsted–Evans–Polanyi relationship for O2 dissociation on Pt(321). Ensemble averaging over available sites and their corresponding rates yields total reaction rates. Predicted apparent activation energies and rate orders are consistent with the experimental observations on single crystal catalysts and are most strongly determined by the coverage dependence of O adsorption rather than the statistical availability of O2 dissociation sites. Rates and rate derivatives are similar on the two surfaces over the range of experimental observation and are predicted to differ more significantly outside this range.