在模型单原子催化剂上,CO诱导的迪默衰变导致了宝石-二甲基的形成
Chunlei Wang1, Panukorn Sombut1, Lena Puntscher1
1Institute of Applied Physics, TU Wien, Vienna, 1040, Austria.
Angewandte Chemie (International ed. in English)
|January 31, 2024
概括
在氧化铁表面上的少数二元分解形成反应性单原子催化剂. 这项研究揭示了这些经常被忽视的物种对于理解催化活性和设计新的单原子催化剂至关重要.
科学领域:
- 表面科学是一门学科.
- 不同质的催化剂.
- 纳米材料是一种纳米材料.
背景情况:
- 单原子催化 (SAC) 对于高效的化学转换至关重要,需要精确控制活性部位的几何结构.
- 模型催化剂,就像单晶表面一样,可以详细研究催化中的结构-活性关系.
- 了解原子层面的反应物协调是推动SAC应用的关键.
研究的目的:
- 调查少数 (Rh) 物种,特别是 (Rh1) 和二极体 (Rh2) 在一氧化碳 (CO) 暴露期间对Fe3O4 (001) 的作用.
- 阐明在Rh1和Rh2位点上CO吸附过程中形成的反应途径和中间物种.
- 为了证明少数物种在催化过程中的重要性,这些物种经常被批量技术遗漏.
主要方法:
- 在室温下利用时间间隔扫描道显微镜 (STM) 来观察Rh adatoms和二次体的动态演变.
- 使用密度函数理论 (DFT) 进行理论比较和理解反应机制.
- 在Fe3O4(001) 模型催化剂表面上研究Rh1和Rh2物种的CO吸附.
主要成果:
- Rh1 基因组仅形成稳定的 Rh1CO 单碳烯基物种,它们的协调适应伪正方形平面几何形状.
- 已观察到Rh1(CO) 2二碳酸物种,但它们仅来源于Rh2二元体的分解.
- 形成Rh1(CO) 2通过不稳定的Rh2(CO) 3中间体进行,突出显示二分体的不稳定性.
结论:
- 少数Rh2二次体在生成反应性配置方面发挥着关键作用,尽管它们通常低于合并方法的检测极限.
- 双重体和小集群的分解可能是一个可行的策略,用于单原子催化产生转移稳定的活性位点.
- 这项工作强调了考虑所有存在的物种的重要性,包括少数物种,以全面了解催化系统.
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