Departamento de Química Física, Universidad de La Laguna, Tenerife, Spain.
Langmuir. 2010 Sep 21;26(18):14655-62. doi: 10.1021/la102505c.
This paper presents a theoretical study of the surface structures and thermodynamic stability of different thiol and sulfide structures present on the palladium surface as a function of the chemical potential of the thiol species. It has been found that as the chemical potential of the thiol is increased, the initially clean palladium surface is covered by a (√3 × √3)R30° sulfur lattice. Further increase in the thiol pressure or concentration leads to the formation of a denser (√7 × √7)R19.1° sulfur lattice, which finally undergoes a phase transition to form a complex (√7 × √7)R19.1° sulfur + thiol adlayer (3/7 sulfur + 2/7 thiol coverage). This transition is accompanied by a strong reconstruction of the Pd(111) surface. The formation of these surface structures has been explained in terms of the catalytic properties of the palladium surface. These results have been compared with X-ray photoelectron spectroscopy results obtained for thiols adsorbed on different palladium surfaces.
本文针对钯表面上不同硫醇和硫化物结构的表面结构和热力学稳定性进行了理论研究，其功能取决于硫醇物质的化学势。研究发现，随着硫醇化学势的增加，最初清洁的钯表面会被（√3×√3）R30°硫晶格覆盖。进一步增加硫醇的压力或浓度会导致更密集的（√7×√7）R19.1°硫晶格的形成，最终会发生相转变，形成复杂的（√7×√7）R19.1°硫+硫醇吸附层（3/7 硫+2/7 硫醇覆盖率）。这种转变伴随着 Pd(111)表面的强烈重构。这些表面结构的形成是根据钯表面的催化特性来解释的。这些结果与不同钯表面上吸附的硫醇的 X 射线光电子能谱结果进行了比较。
