氯在Cu(100)面上的吸附及其对氧共吸附的影响的电子能谱研究

利用UPS、XPS、AES、△φ和热脱附等方法,研究了室温、低分压下氯在Cu(100)面上的吸附行为以及它对氧共吸附的影响。氯解离化学吸附在铜表面上,其吸附过程包括初始快速吸附,然后缓慢增加至饱和两个步骤。吸附引起铜表面轻微氧化,但表面没有重排,即使升温氯原子也没有进一步向下扩散,热脱附的唯一产物是氯原子。室温下,氯的预吸附降低甚至完全阻止了氧的接续吸附;而预吸附氧至饱和也不会阻碍氯的接续吸附,氯的接续吸附促使氧原子进入体相和铜原子向表层扩散。

The Study of Chlorine Adsorption on Copper (100) and Its Effect on Coadsorbted Oxygen by Electron Spectroscopy

The adsorption of chlorine and the coadsorbtion of chlorine with oxygen on Cu(100) surface are studied with AES, UPS, XPS and work function measurements. Chlorine adsorbs dissociatively and remains chemisorb on the surface. The chlorine uptake first increases rapidly and then slows down to reach a saturation value. Chlorine adsorption induces slight oxidation of Cu at 300 K and does not cause any chlorine atoms into the bulk at low pressure of chlorine even when the surface is heated to a high temperature. Only the atomic chlorine is found as the desorption species of the Cl/Cu(100) system. At 300 K, the chlorine preadsorption on surface strongly reduces or completely suppresses any further uptake of oxygen above certain coverage of chlorine. In contrast to chlorine, oxygen preadsorption does not have any inhibiting effect on the additional adsorption of chlorine, even for oxygen saturated surfaces. The chlorine adsorption drives the preadsorbed oxygen into the subsurface region rather than displace it into the vacuum.