完全分散的Rh组合催化剂以增强低温活动
Hojin Jeong1, Geonhee Lee2, Beom-Sik Kim1
1Department of Chemical and Biomolecular Engineering , Korea Advanced Institute of Science and Technology , Daejeon 34141 , South Korea.
Journal of the American Chemical Society
|July 6, 2018
概括
研究人员开发了高分散的 (Rh) 催化剂,其性能优于单原子催化剂 (SAC) 的低温氧化反应. 这些催化剂显示出增强的原子效率和活性,这对于工业应用至关重要.
科学领域:
- 不同质的催化
- 材料科学
- 表面化学
背景情况:
- 珍贵金属催化剂至关重要但代价昂贵;尽量减少它们的使用是关键目标.
- 单原子催化剂 (SAC) 提供最大的原子效率,但缺乏某些反应的合并点.
- 需要多个相邻的金属原子的反应不能被SAC催化.
研究的目的:
- 开发具有集体位点的高度分散的 (Rh) 催化剂.
- 与SAC相比,评估新的Rh催化剂的催化性能.
- 了解催化剂形成的机制及其对活动的影响.
主要方法:
- 在750°C进行25小时的Rh/CeO2的水热处理.
- 催化剂分散和Rh原子聚合状态的表征 (ENS与SAC).
- 在低温中测试CO,C3H6和C3H8的催化活性,包括同时发生的反应.
主要成果:
- 在水热处理后,通过非隔离的Rh原子 (ENS) 实现了近100%的分散.
- 与Rh SAC不同的是,ENS催化剂有效催化了C3H6和C3H8的氧化.
- 与SAC相比,ENS催化剂在同时氧化CO,C3H6和C3H8时显示出明显较低的灭光温度 (T20).
结论:
- 与SAC相比,开发的ENSRh催化剂具有较高的低温氧化活性.
- 水热处理可促进Rh原子脱离,并防止通过表面基团进行重聚.
- 这种完全分散的ENS催化剂为特定反应提供了高原子效率和增强的催化性能.
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