Department of Physics, South China University of Technology, Guangzhou 510640, P. R. China.
Phys Chem Chem Phys. 2011 Aug 28;13(32):14466-75. doi: 10.1039/c1cp20974d. Epub 2011 Jul 7.
NO co-adsorption with X (X = Na, O, S, and Cl) on Au and Pd(111) surfaces is studied using density functional theory (DFT) calculations to get a deeper insight into the extraordinary sulfur enhanced adsorption on the Au surface. It is found that both electronegative and electropositive adatoms can enhance NO adsorption on Au(111). In Na + NO/Au(111), the strong electrostatic attraction between Na and NO dominates and stabilizes NO adsorption, though Na-induced surface negative charging weakens NO adsorption. In (O, S, Cl) + NO/Au, the electronegative atoms would induce a slight surface distortion and enhance NO adsorption accordingly. NO adsorption on Pd(111) is enhanced by Na, but weakened by electronegative species. We suggest that the unique features of noble metals, i.e., the narrow DOS at the Fermi level (E(F)) and the deep buried d-band center, should play an important role in the promotion of NO adsorption on their surface as the CO case.
采用密度泛函理论（DFT）计算研究了 X（X = Na、O、S 和 Cl）在 Au 和 Pd(111)表面上的共吸附，以更深入地了解 Au 表面上硫的增强吸附。结果发现，无论是带负电荷还是带正电荷的吸附原子都可以增强 Au(111)上的 NO 吸附。在 Na+NO/Au(111)中，Na 和 NO 之间的强静电吸引作用占主导地位并稳定了 NO 的吸附，尽管 Na 诱导的表面负电荷削弱了 NO 的吸附。在（O、S、Cl）+NO/Au 中，电负性原子会引起轻微的表面变形，从而相应地增强 NO 的吸附。Na 增强了 NO 在 Pd(111)上的吸附，但电负性物种则削弱了其吸附。我们认为，贵金属的独特性质，即费米能级（E(F)）处的窄 DOS 和深埋的 d 带中心，应该在促进其表面上的 NO 吸附方面发挥重要作用，就像 CO 的情况一样。
