有悬浮氨基的分子复合物,用于选择性电催化将二氧化碳减少为酸
Souvik Roy1, Bhaskar Sharma2, Jacques Pécaut3
1Laboratoire de Chimie et Biologie des Métaux, Université Grenoble Alpes , CEA, CNRS, 17 rue des Martyrs, 38000 Grenoble, France.
Journal of the American Chemical Society
|February 17, 2017
概括
新的催化剂有效地将二氧化碳 (CO2) 转化为酸. 这些地球上丰富的催化剂具有很高的选择性和活性,为二氧化碳减少提供了有希望的途径.
科学领域:
- 催化剂
- 电化学
- 有机金属化学
背景情况:
- 开发有效的二氧化碳 (CO2) 减排催化剂对于缓解气候变化和实现可持续化学合成至关重要.
- 分子催化剂为选择性二氧化碳转化提供可调节的特性,但许多都依赖贵金属或缺乏足够的活性和稳定性.
研究的目的:
- 合成和表征一种新的地球丰富的,基于的分子催化剂,用于选择性减少二氧化碳到酸.
- 调查这些催化剂的结构-活性关系,重点关注与悬浮氨基组的二素连接体的作用.
主要方法:
- 用定制的二联体合成和表征复合物 ([CpCo(PR2NR'2) I]+).
- 在二甲基形式胺 (DMF) /水混合物的催化性能的电化学评估,包括法拉第效率和超电位测量.
- 使用密度函数理论 (DFT) 模拟和对联体效应的分析的机制研究.
主要成果:
- 新的催化剂在中度超电位 (500-700 mV) 时具有高选择性 (> 90%).
- 催化剂活动受到连接物电子学和基本性的显著影响,性能最好的复合物达到>1000s-1的转换频率.
- 机理学研究证实了氨基群作为质子继电器的作用,以及它们通过键结合稳定关键中间体.
结论:
- 这一系列复合物代表了CO2转化为甲酸的极具前景的催化剂类.
- 连接体设计,特别是结合电子捐赠和基本氨基功能,是优化催化性能的关键.
- 需要进一步改善催化剂的稳定性,以充分发挥它们在工业应用中的潜力.
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