Reaction of gaseous oxygen with adsorbed carbon on Pt{110}(1×2)
Reaction of gaseous oxygen with adsorbed carbon on Pt{110}(1×2)
复制标题
气态氧与 Pt{110}(1×2) 上吸附碳的反应
DOI：
--
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
D. King
中科院分区：
文献类型：
--
作者：
A. Walker;D. King
使用分子束技术研究了 Pt{110}(1×2) 上的 C 氧化反应。反应产物是CO和CO2。随着表面温度从 550 K 增加到 750 K，产生的 CO2 比例从 ∼50% 减少到 <1%。当氧气第一次撞击表面时，观察到 CO 的形成速率立即上升（⩽0.1 s），然后缓慢上升至最大值，然后随着 C 吸附层的耗尽而急剧下降。 CO2 的产生在可测量的延迟后开始。角度分辨产物分布测量表明，CO 在以与表面法线成 32° 角为中心的尖锐波瓣中解吸，拟合为 cosn(θ−32)，其中 n=50±5。 C 氧化反应位点由 (111) 微面识别。结论是两个过程是有效的，朗缪尔-欣谢尔伍德机制和二氧化碳脉冲解吸的反应。
The C oxidation reaction on Pt{110}(1×2) has been investigated using molecular beam techniques. The reaction products are CO and CO2. As the surface temperature is increased from 550 to 750 K, the proportion of CO2 produced decreases from ∼50% to <1%. When oxygen first impinges on the surface, the formation rate of CO is observed to rise immediately (⩽0.1 s), and then rise more slowly to a maximum before decreasing sharply as the C adlayer is depleted. The production of CO2 is initiated after a measurable delay. Angle-resolved product distribution measurements demonstrate that CO desorbs in a sharp lobe centered at an angle of 32° to the surface normal, fitted to cosn(θ−32), where n=50±5. The C oxidation reaction site is identified with the (111) microfacets. It is concluded that two processes are operative, a Langmuir–Hinshelwood mechanism and a reaction in which CO is impulsively desorbed.