在附近的Cu表面上CO2分子的低温解离
Takanori Koitaya1, Yuichiro Shiozawa2, Yuki Yoshikura2
1Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-Ku, Kyoto 606-8502, Japan. koitaya.takanori.5j@kyoto-u.ac.jp.
Physical chemistry chemical physics : PCCP
|March 6, 2024
概括
在附近的铜表面,在低温下观察到二氧化碳分裂成一氧化碳. 这种反应是由共同吸收的氧气促进的,导致二氧化碳转换的诱导期.
科学领域:
- 表面科学是一门学科.
- 不同质的催化剂.
- 物理化学 物理化学
背景情况:
- 了解金属表面的二氧化碳 (CO2) 反应对于催化和环境应用至关重要.
- 与平面相比,旁边铜 (Cu) 表面表现出独特的反应性.
研究的目的:
- 研究CO2在附近Cu表面的低温反应.
- 确定影响二氧化碳解离和随后反应的因素.
主要方法:
- 红外反射吸收光谱法 (IRAS) 是一种技术.
- 扫描道显微镜 (STM) 的使用
- 在X射线光电子光谱学 (XPS) 中.
- 四极质谱法 (QMS) 是一种四极质谱法.
主要成果:
- 在80-90K之间的Cu (997) 和Cu (977) 表面上观察到二氧化碳分裂成CO,但在Cu (111) 上没有观察到.
- 协同吸收的氧气促进了解离,创造了一个感应期.
- 二氧化碳和被物理吸收的二氧化碳是主要吸附物;原子氧含量很低.
- 二氧化碳的形成主要是由于在超高真空中与剩余的二氧化碳进行氧气交换反应.
结论:
- 周围的Cu表面在低温下促进二氧化碳解离,这一过程由共吸收氧气增强.
- 反应机制涉及初始的低速率在干净的表面,其次是氧气促进解离.
- 真空室中的残留CO在通过氧气交换观察到的CO形成中起着重要作用.
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