Ab initio studies of hydrogen desorption from low index magnesium hydride surface
Ab initio studies of hydrogen desorption from low index magnesium hydride surface
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DOI：
10.1016/j.susc.2006.02.019
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发表时间：
2006-05-01
期刊：
影响因子：
1.9
通讯作者：
Lu, G. Q.
中科院分区：
文献类型：
--
作者：
Du, A. J.;Smith, Sean C.;Lu, G. Q.
用密度泛函理论（DFT）计算研究了MgH_2（001）和MgH_2（110）低指数表面。发现MgH_2（110）面比MgH_2（001）面更稳定，这与实验观察相一致。的H-2解吸障碍不同，这取决于暴露的晶体表面，也涉及特定的H原子的网站，他们被发现是普遍较高的，由于热力学稳定性的MgH 2，系统，和更大的MgH 2（001）表面。从MgH 2（110）表面的一个面内和一个桥接H原子的重组解吸的途径被认为是最低的能垒之间的计算（172 KJ/mol），是在良好的协议与实验估计。(c)2006 Elsevier B. V.保留所有权利。
The low index Magnesium hydride surfaces, MgH2(001) and MgH2(110), have been studied by ab intio Density Functional Theory (DFT) calculations. It was found that the MgH2(110) surface is more stable than MgH2(001) surface, which is in good agreement with the experimental observation. The H-2 desorption barriers vary depending on the crystalline surfaces that are exposed and also the specific H atom sites involved-they are found to be generally high, due to the thermodynamic stability of the MgH2, system, and are larger for the MgH2(001) surface. The pathway for recombinative desorption of one in-plane and one bridging H atom from the MgH2(110) surface was found to be the lowest energy barrier amongst those computed (172 KJ/mol) and is in good agreement with the experimental estimates. (c) 2006 Elsevier B.V. All rights reserved.