通过从单原子到双原子催化转向反应途径对酒精脱的催化活性增强
Ce Liu1, Teng Li1, Xingchao Dai1
1State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, No. 18, Tianshui Middle Road, Lanzhou 730000, China.
Journal of the American Chemical Society
|March 9, 2022
概括
引入双原子催化剂 (DAC) 与结合的Fe-Co原子进行酒精脱. 与单原子催化剂相比,这种FeCo-DAC催化剂的反应性和选择性更强.
科学领域:
- 不同质的催化
- 材料科学
- 可持续化学
背景情况:
- 单原子催化剂 (SAC) 具有高原子利用率,但其内在反应性可能受到限制.
- 修改单原子位点与邻近的金属原子形成双原子催化剂 (DAC) 是提高催化性能的一种新策略.
- 酒精脱是有机合成中的关键转化,通常需要高效和选择性的催化系统.
研究的目的:
- 开发和研究一种用于酒精脱的新型Fe-Co双原子催化剂 (DAC).
- 将FeCo-DAC与相应的单原子催化剂 (Fe-SAC和Co-SAC) 的催化活性和机制进行比较.
- 阐明双金属位点在增强反应性能和改变反应途径中的作用.
主要方法:
- 合成具有FeCoN6(OH) 组合结构和100%金属分散的FeCo-DAC催化剂.
- 在无氧化剂条件下使用各种基质对酒精脱的催化性能进行评估.
- 动力学研究和计算建模 (例如,DFT) 了解反应机制和激活能量.
主要成果:
- 与Fe-SAC和Co-SAC相比,FeCo-DAC的活性和选择性显著更高,产品产量高达98%.
- 催化剂证明了广泛的适用性,成功地将各种醇和酸醇转化为相应的脱产品.
- 动力分析显示FeCo-DAC的激活能量较低,计算研究证实了双原子位点促进的独特反应途径.
结论:
- 在FeCo-DAC中相邻的Fe和Co原子之间的协同作用对于提高酒精脱效率至关重要.
- FeCo-DAC有效切换反应机制,从而提高催化性能和降低能量障碍.
- 这项工作突显了DAC作为高效和选择性化学转换的先进催化材料的潜力.
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