高选择性Fe-催化对水的固定通过Sm(II) 具有量身定制的氧化潜力的试剂和pKa
Emily A Boyd1, Jonas C Peters1
1Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, California 91125, United States.
Journal of the American Chemical Society
|June 28, 2023
概括
研究人员控制了降解反应中的产品选择性,通过使用强烈的降解剂,偏爱素 (N2H4) 与氨 (NH3). 这一发现为催化固定提供了新的见解.
科学领域:
- 催化剂
- 无机化学
- 电化学
背景情况:
- 控制小分子的多质子,多电子减少的产品选择性对于催化是至关重要的.
- 对氨 (NH3) 与 (N2H4) 的降解反应 (N2RR) 的选择性不太清楚.
- 铁催化剂通常有利于在N2RR中产生NH3.
研究的目的:
- 调查在N2RR中逆转选择性的条件.
- 使用铁催化剂,优于氨 (NH3) 产生素 (N2H4).
- 了解N2RR中选择性控制的机制基础.
主要方法:
- 开发条件以逆转三酸铁催化剂 (Fe) 的选择性.
- 使用强度降解的SmII-(2-pyrrolidone) 核心,并使用六酸二基宏环联体 (Sm-PH) 作为原子供体.
- 采用了包括光谱在内的机械学研究来探测反应途径.
主要成果:
- 通过用Sm-PH系统取代中度减热剂和强酸来实现专有的N2H4生产 (>99:1).
- 保持高的催化剂活性和效率,每Fe的N2H4等值高达69%,固定N产量高达67%.
- 与NH3选择性条件相比,观察到N2H4生产的超电位降低了700mV.
结论:
- 在开发的Sm驱动条件下,N2H4是动力产物.
- 选择性取决于铁化2-) 种 (FeNNH2):质子化产生NH3,而一个电子的减少产生N2H4.
- SmIII与离子FeN2结合可能在催化功效中起作用.
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