Microkinetic simulations of the oxidation of CO on Pd based nanocatalysis: a model including co-dependent support interactions
Microkinetic simulations of the oxidation of CO on Pd based nanocatalysis: a model including co-dependent support interactions
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DOI：
10.1039/b805688a
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发表时间：
2008-01-01
影响因子：
3.3
通讯作者：
Heiz, Ulrich
中科院分区：
文献类型：
--
作者：
Harding, Christopher J.;Kunz, Sebastian;Heiz, Ulrich
使用反应的微动力学模拟对使用负载在薄 MgO 薄膜上的质量选择的 Pd(13) 簇催化 CO 氧化进行建模。系统模型包括反向溢出计算，该计算本质上被纳入动力学公式中。溢出模型基于捕获区方法，包括对动力学方程变量的相互依赖。实验值是使用双脉冲分子束测量确定的，并在一定温度范围内记录。该实验允许将转换频率和反应概率确定为摩尔分数的函数。动力学模型与实验数据的比较给出了极好的一致性，并强烈强调了底物效应的重要性。特别是，阐明了 Pd 簇的低温催化作用的起源。该模型允许预测摩尔分数和温度相关值，例如这些簇的粘附系数。
The catalysed oxidation of CO using mass-selected Pd(13) clusters supported on thin MgO films was modelled using a microkinetic simulation of the reaction. The model of the system includes reverse spill-over calculations which were intrinsically incorporated into the formulation of the kinetics. The spill-over model is based on a capture-zone approach including a co-dependence on the variables of the kinetic equations. The experimental values were determined using dual pulsed-molecular beam measurements and recorded at a range of temperatures. The experiment allowed the turn-over frequency and reaction probability to be determined as a function of mole fraction. Comparison of the kinetic model with the experimental data gives excellent agreement and strongly highlights the importance of substrate effects. In particular, the origin of the low temperature catalysis of the Pd clusters is elucidated. The model allows the mole fraction and temperature dependent values such as the sticking coefficients for these clusters to be predicted.