Methane activation on Ni(111):: Effects of poisons and step defects
Methane activation on Ni(111):: Effects of poisons and step defects
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DOI：
10.1016/j.susc.2005.05.057
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发表时间：
2005-10-01
期刊：
影响因子：
1.9
通讯作者：
Norskov, JK
中科院分区：
文献类型：
--
作者：
Abild-Pedersen, F;Lytken, O;Norskov, JK
我们从理论和实验上研究了甲烷在Ni(111)表面的阶梯和台阶上的解离。利用密度泛函理论(DFT)总能量计算结合超高真空(UHV)实验，我们发现阶梯比阶梯显示出更高的活度。此外，我们还研究了表面存在的碳和硫如何使台阶失活，只留下梯田活跃。结果表明，在500K时，甲烷在台阶和台阶上的本征吸附几率分别为2.8×10~(-7)和2.1×10~(-9)，与我们计算的17kJ/mol的活化能差完全一致。(C)2005 Elsevier B.V.保留所有权利。
We have, theoretically and experimentally, investigated the dissociation of methane on the terraces and steps of a Ni(1 11) surface. Using Density Functional Theory (DFT) total energy calculations combined with Ultra High Vacuum (UHV) experiments, we find that the steps exhibit a higher activity than the terraces. We have, furthermore, investigated how carbon and sulfur present on the surface will deactivate the steps, leaving only the terraces active. We find the intrinsic sticking probabilities of methane on the steps and terraces at 500 K to be 2.8 x 10(-7) for the steps and 2.1 x 10(-9) for the terraces, in complete agreement with our calculated difference in activation energy of 17 kJ/mol. (c) 2005 Elsevier B.V. All rights reserved.