Kinetic mechanism of methanol decomposition on Ni(111) surface: a theoretical study.
Kinetic mechanism of methanol decomposition on Ni(111) surface: a theoretical study.
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DOI：
10.1021/jp0463969
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发表时间：
2005-06
期刊：
影响因子：
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通讯作者：
Guichang Wang;Yu-Hua Zhou;Y. Morikawa;J. Nakamura;Zunsheng Cai;Xuehui Zhao
中科院分区：
文献类型：
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作者：
Guichang Wang;Yu-Hua Zhou;Y. Morikawa;J. Nakamura;Zunsheng Cai;Xuehui Zhao
采用密度泛函-广义梯度近似（DFT-GGA）赝势方法和重复板模型研究了甲醇在Ni（111）表面的分解。得到了可能物质的吸附能和可能参与的基本反应的活化能垒。Ni表面上的主要反应途径是CH(3)OH中的O-H键断裂，并通过从CH(3)O中逐步提取氢进一步分解产生的甲氧基物质为CO和H。从甲氧基中提取氢是限制速率的步骤。我们还证实了C-O和C-H断键路径具有更高的能垒，它们分别导致表面甲基和羟基以及羟甲基和原子氢的形成。因此，最终产物是吸附的CO和H原子。
The decomposition of methanol on the Ni(111) surface has been studied with the pseudopotential method of density functional theory-generalized gradient approximation (DFT-GGA) and with the repeated slab models. The adsorption energies of possible species and the activation energy barriers of the possible elementary reactions involved are obtained in the present work. The major reaction path on Ni surfaces involves the O-H bond breaking in CH(3)OH and the further decomposition of the resulting methoxy species to CO and H via stepwise hydrogen abstractions from CH(3)O. The abstraction of hydrogen from methoxy itself is the rate-limiting step. We also confirm that the C-O and C-H bond-breaking paths, which lead to the formation of surface methyl and hydroxyl and hydroxymethyl and atom hydrogen, respectively, have higher energy barriers. Therefore, the final products are the adsorbed CO and H atom.