Adsorption and Dissociation of O2 on Gold Surfaces: Effect of Steps and Strain
Adsorption and Dissociation of O2 on Gold Surfaces: Effect of Steps and Strain
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DOI：
10.1021/jp034380x
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发表时间：
2003-08
影响因子：
3.3
通讯作者：
Ye Xu;M. Mavrikakis
中科院分区：
文献类型：
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作者：
Ye Xu;M. Mavrikakis
采用周期性自洽密度泛函理论（GGA-PW 91）方法研究了应变和台阶金表面上分子氧的解离活化。虽然我们发现分子氧不吸附在Au（111）上，但它确实与拉伸10%的Au（111）表面以及拉伸和未拉伸的Au（211）表面结合，尽管结合很弱。在所有三个表面上最稳定的分子状态都具有顶-桥-顶构型，并且携带大约一半的气相O2磁矩。在拉伸10%的Au（111）、未拉伸的Au（211）和拉伸10%的Au（211）上，O2的结合能分别为−0.08、−0.15和−0.26 eV，O2解离的活化能分别为1.37、1.12和0.63 eV。台阶和拉伸应变都增强了原子氧和分子氧的吸附。未拉伸和拉伸的Au（211）之间的比较表明，拉伸应变的增强效应在台阶边缘上不如在平坦平台上显著。这...
The activation of dioxygen via dissociation on strained and stepped gold surfaces has been studied using periodic self-consistent (GGA-PW91) density functional theory (DFT) calculations. Although we find that molecular oxygen does not adsorb on Au(111), it does bind, albeit weakly, to an Au(111) surface stretched by 10% as well as to Au(211) surfaces both stretched and unstretched. The most stable molecular states on all three surfaces have the top−bridge−top configuration and carry about half of the magnetic moment of gas-phase O2. On 10%-stretched Au(111), unstretched Au(211), and 10%-stretched Au(211), the binding energies of O2 are −0.08, −0.15, and −0.26 eV, respectively, and the activation energies of O2 dissociation are 1.37, 1.12, and 0.63 eV. Both steps and tensile strain enhance the adsorption of atomic and molecular oxygen. A comparison between unstretched and stretched Au(211) indicates that the enhancing effect of tensile strain is less pronounced on the step edge than on the flat terrace. Th...