Density Functional Theory Study of Atomic and Molecular Oxygen Adsorption on Au Clusters

作者：Guo Xiao Wei; Teng Bo Tao^*; Yuan Jin Huan; Zhao Yun; Zhao Yue; Liu Sha

来源：Acta Physico - Chimica Sinica, 2011, 27(5): 1068-1074.

• Oxygen atom and molecule
• Adsorption
• Reaction
• Au cluster
• Density functional theory

The adsorption behaviors of O and O(2) on charged and neutral Au(19) and Au(20) clusters were systematically investigated by density functional theory (DFT) with Dmol(3) program. Our results indicate that the adsorption energies of O on the hollow sites of Au(19) are higher than those on Au(20); while those on the side-bridge sites of the Au(19) and Au(20) clusters are similar. For negatively charged clusters, the adsorption energies of O and O(2) are higher than those for neutral and positive clusters. The O - O bond lengths of the adsorbed O(2) on the Au(19) and Au(20) clusters with different charges show a similar trend to the adsorption energy, that is, the O - O bond lengths on Au(19)(-) are longer than those on the Au(19) and Au(19)(+) clusters. Population analysis shows that more electrons transfer to the adsorbed O and O(2) from the Au(19)(-) and Au(20)(-) clusters, which indicates stronger interactions compared with the neutral or positive clusters. Charge density difference (CDD) analysis for O(2) on the Au(19) and Au(20) clusters suggests that electrons of the Au(19) and Au(20) clusters transfer to the pi* orbital of O(2), upon which the O - O bonds are activated. The dissociation reaction barrier of O(2) on Au(19)(-) is 1.33 eV, which is lower than those on Au(19) (1.86 eV) and Au(19)(+) (2.27 eV).

• 出版日期2011-5
• 单位浙江师范大学