通过调节Rh单个原子与反应物的协调来抑制金属水和烧结
Zhounan Yu1,2, Shengxin Zhang1,2, Leilei Zhang1
1CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Journal of the American Chemical Society
|April 19, 2024
概括
单原子Rh催化剂 (SAC) 显示出水合形成的前景,但受到聚合和浸的影响. 这项研究显示CO和化物导致Rh不稳定,而化物则稳定催化剂超过100小时.
科学领域:
- 不同质的催化
- 材料科学
背景情况:
- 化是一种主要的工业过程,依赖于同质的催化剂,在分离和回收方面存在挑战.
- 不同质的单原子催化剂 (SAC) 具有高活性和区域选择性,但它们的稳定性,特别是金属聚合和液,仍然令人担忧.
研究的目的:
- 阐明 Rh1 SAC 中 (Rh) 聚合和浸出的机制.
- 为了确定影响SAC稳定性的因素.
主要方法:
- 使用扩散反射红外里埃变换光谱,X射线吸附细结构和扫描传输电子显微镜研究了Rh1@silicalite-1 SACs的结构演变.
- 在各种吸附物条件下 (CO,H2,基,基) 进行了动态研究,以了解Rh聚合和出机制.
主要成果:
- 强烈吸附CO和化物,以及Rh3+减少CO/H2,通过削弱Rh-支持结合诱导Rh聚合和液.
- 基因通过竞争性吸附和促进Rh集群分解来抵消聚合和液.
- 高度可以稳定Rh SACs,使其在100小时以上的运行时间内不发生聚合和液.
结论:
- Rh SACs的稳定性严重依赖于吸附物相互作用和Rh氧化状态.
- 涉及高基度的策略有效地提高了Rh SAC在水合制中的长期稳定性,解决了关键的工业挑战.
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