Quantum Chemical Molecular Dynamics Study of the Water–Gas Shift Reaction on a Pd/MgO(100) Catalyst Surface
Quantum Chemical Molecular Dynamics Study of the Water–Gas Shift Reaction on a Pd/MgO(100) Catalyst Surface
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DOI：
10.1021/jp310946x
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发表时间：
2013-03
影响因子：
3.7
通讯作者：
Farouq Ahmed;R. Miura;N. Hatakeyama;H. Takaba;A. Miyamoto;D. Salahub
中科院分区：
文献类型：
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作者：
Farouq Ahmed;R. Miura;N. Hatakeyama;H. Takaba;A. Miyamoto;D. Salahub
采用紧束缚-量子化学分子动力学（TB-QCMD）方法研究了Pd/MgO（100）催化剂表面的水煤气变换反应。CO的分子吸附。与此相反，我们观察到，H2O吸附发生第一次分子，但分子然后在表面上解离。生成的羟基与预吸附的CO反应形成OCOH中间体和单个H原子。该过程与初始羟基化步骤相关，并且是催化水解机制的一部分。在分子动力学模拟过程中，OCOH中间体转化为H-CO2类分子，HCO 2最终分解为CO2和H。随后，所产生的H与先前解离的单个H原子（从H-OH解离释放的H）相互作用并形成WGS产物H-H分子。在模拟过程中，观察到CO2从负载的Pd簇上脱附，而H2分子仍然附着在Pd簇上。的几何和dissociat.
The water–gas shift (WGS) reaction on a Pd/MgO(100) catalyst surface was studied using the tight binding-quantum chemical molecular dynamics (TB-QCMD) method. Molecular adsorption of CO was observed. In contrast, we observed that H2O adsorption occurs first molecularly but the molecule then dissociates on the surface. The resultant hydroxyl group reacts with preadsorbed CO to form an OCOH intermediate and a single H atom. This process is relevant as the initial hydroxylation step, and it is part of the catalyzed hydrolysis mechanism. During the molecular dynamics simulation the OCOH intermediate inverted into an H–CO2 like molecule and finally HCO2 decomposed to CO2 and H. Later on, the resultant H interacts with the previously dissociated single H atom (H released from the H–OH dissociation) and forms the WGS product H–H molecule. It was observed that the CO2 desorbed from the supported Pd cluster while the H2 molecule remains attached to the Pd cluster during the simulation. The geometries and dissociat...