在Rh1/Fe3O4上通过二化物形成激活气 (001) 单原子催化剂
Chunlei Wang1, Panukorn Sombut1, Lena Puntscher1
1Institute of Applied Physics, TU Wien, Vienna, Austria.
铁氧化物上孤立的原子通过二化物中间体激活,模仿同质催化剂,在没有溢出的情况下弥合同质和异质催化机制.
科学领域:
- 不同质的催化剂.
- 表面科学是一门科学.
- 一个原子的催化剂.
背景情况:
- 激活对于化反应至关重要.
- 异质催化通常涉及金属纳米颗粒上的离合性吸附.
- 同质催化剂通过单一金属中心的二化物或二中间体激活H2.
研究的目的:
- 通过在Fe3O4上分离的Rh adatoms对Fe3O4的激活进行研究.
- 阐明单个原子水平上激活的机制.
- 建立同质和异质催化剂之间的机械联系.
主要方法:
- 温度编程绝吸法 (TPD) 是指温度编程绝吸法.
- 在X射线光电子光谱学 (XPS) 中.
- 扫描道显微镜 (STM) 的使用
- 同位素交换实验的实验
- 密度函数理论 (DFT) 的计算.
- 随机相近似计算 (RPA) 的计算.
主要成果:
- 在Fe3O4(001) 上隔离的Rh基因组激活,形成稳定的二化物种.
- 吸附很强 (≈1 eV),并且仅在孤立的Rh位点局部化.
- 没有观察到原子溢出.
- DFT和RPA计算证实了无障碍的转化到二化物及其稳定性.
结论:
- 单个Rh原子通过二化物通路分裂,类似于同质催化剂.
- 这项研究建立了同质和异质催化剂之间的机制桥梁.
- 孤立的单个原子可以表现出与纳米粒子不同的独特反应性.
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