We investigated the room-temperature chemisorption of oxygen on Cu(1 0 0) and Cu(1 1 1) using ambient-pressure X-ray photoelectron spectroscopy (APXPS). A shoulder-to-shoulder comparison between the oxygen-gas titration on the two surfaces reveals that Cu(1 0 0) is the more active for oxygen dissociative chemisorption when the surfaces are clean. The (2 $\sqrt{2}$ × $\sqrt{2}$)R45^o missing-row reconstruction appears in Cu(1 0 0)’s LEED image after about 10⁴ Langmuir of oxygen exposure, whereas on Cu(1 1 1), no long-range ordering was observed throughout the whole experiment. An oxide layer consisting of cuprous and cupric oxide shows up on Cu(1 1 1) at an oxygen exposure that is significantly lower than for Cu(1 0 0). This observation suggests that the presence of (2 $\sqrt{2}$ × $\sqrt{2}$)R45^o missing-row reconstruction layer slows down Cu(1 0 0) oxidation. Literature has widely reported that surface morphology influences the copper oxidation process. This study provides an XPS demonstration that copper surface oxide formation in O₂ at room temperature depends on the surface crystallographic orientation.

我们使用环境压力 X 射线光电子能谱 (APXPS)研究了氧在 Cu(1  0  0) 和 Cu(1  1 1) 上的室温化学吸附。 两个表面上的氧气滴定之间的并肩比较表明，当表面清洁时，Cu(1  0  0) 对氧离解化学吸附的活性更高。（2$\sqrt{2}$ × $\sqrt{2}$)R45 ^o缺失行重建出现在 Cu(1  0  0) 的 LEED 图像中，经过大约 10 ⁴ Langmuir 氧暴露，而在 Cu(1  1  1) 上，在整个实验过程中没有观察到长程排序。在氧暴露量明显低于 Cu(1 0 0) 的情况下，由亚铜和氧化铜组成的氧化物层出现在 Cu(1  1 1) 上。这一观察表明存在 (2   $\sqrt{2}$ × $\sqrt{2}$)R45 ^o缺失行重建层减缓了 Cu(1  0  0) 的氧化。文献广泛报道表面形态影响铜氧化过程。该研究提供了 XPS 证明，即室温下O ₂中铜表面氧化物的形成取决于表面晶体取向。