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利用光电子能谱技术研究了室温下Ｃｅ膜表面的氧化，分析了在不同氧气暴露量下，稀土金属Ｃｅ氧化状态和样品功函数的变化。结果表明，在Ｏ２吸附的过程中，生成两种Ｃｅ的氧化物。在低的暴露量时，氧在Ｃｅ表面的吸附十分迅速，生成Ｃｅ２Ｏ３。同时，Ｃｅ２Ｏ０３中的Ｃｅ３ｄ和Ｏｌｓ谱峰随着氧气暴露量的增加向低结合能方向漂移。在高的暴露量下，氧在表面的吸附趋于缓慢，表面的Ｃｅ２Ｏ３被氧化成ＣｅＯ２。通过对样品加热，能使得四价的Ｃｅ重新转变回三价。功函数随着Ｏ２的暴露量增加先下降后上升。
The oxidation of Ce surface at room temperature was studied by using photoelectron spectroscopy. The oxidation state of Ce and the work function of Ce under different oxygen exposure were analyzed. The results show that during the adsorption of O2 two oxides of Ce are formed. At low exposures, the adsorption of oxygen on the Ce surface is very rapid, producing Ce2O3. At the same time, Ce3d and Ols peaks in Ce2O03 shift toward low binding energy with the increase of oxygen exposure. At high exposures, the adsorption of oxygen on the surface tends to be slow, and the surface Ce2O3 is oxidized to CeO2. By heating the sample, the tetravalent Ce can be redirected back to the trivalent state. The work function first decreases and then increases with the increase of O2 exposure.