First principles study of methane decomposition on B5 step-edge type site of Ru surface
First principles study of methane decomposition on B5 step-edge type site of Ru surface
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DOI：
10.1088/1361-648x/aa66c7
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发表时间：
2017-05-10
影响因子：
2.7
通讯作者：
Kasai, Hideaki
中科院分区：
文献类型：
--
作者：
Arevalo, Ryan Lacdao;Aspera, Susan Menez;Kasai, Hideaki
许多产生各种碳氢化合物和醇的化学反应都涉及甲烷中 C-H 键的断裂。在本文中，我们使用基于色散校正密度泛函理论的第一原理计算分析了该分子在 Ru 表面 B-5 阶梯边缘型位点上的分解。发现甲烷在表面上有弱吸附，其特征在于其 sp 态与 Ru-dxz、yz、zz 态的杂化。解离吸附在能量上优于分子甲烷吸附，从而产生 CH 碎片。由于在电子未占据的反键态上普遍存在低能 sp-d 键合相互作用，CH 被强烈吸附在表面上。这种高度稳定的 CH 需要比 CH4 更高的 C-H 键裂解激活势垒。
Many chemical reactions that produce a wide range of hydrocarbons and alcohols involve the breaking of C-H bonds in methane. In this paper, we analyzed the decomposition of this molecule on the B-5 step-edge type site of Ru surface using first principles calculations based on dispersion-corrected density functional theory. Methane was found to be weakly adsorbed on the surface, characterized by the hybridization of its sp states with Ru-dxz,yz,zz states. Dissociative adsorption is energetically preferred over molecular methane adsorption, resulting in CH fragment. CH is strongly adsorbed on the surface due to the prevalence of low-energy sp-d bonding interaction over the electron-unoccupied anti-bonding states. This highly stable CH requires higher activation barrier for C-H bond cleavage than CH4.