复合体中Trans效应的动力学提供了对控制CO2电还原活性和稳定的因素的洞察
Sergio Gonell1, Eric A Assaf1, Kyle D Duffee1
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States.
Journal of the American Chemical Society
|April 18, 2020
概括
具有强大的转变效应和氧化还原活性联体的鲁复合物加速电化学二氧化碳的减少. 动力学研究显示,N-异环碳联体可提高有效转化二氧化碳的催化速率.
科学领域:
- 无机化学
- 电化学
- 催化剂
背景情况:
- 开发高效的分子电催化剂以减少二氧化碳对于可持续能源技术至关重要.
- 了解连接物特性和催化活性之间的相互作用是催化剂设计的关键.
- 由于其可调节的电子性质,复合物是二氧化碳电减的有希望的候选物.
研究的目的:
- 研究复合物的强变效连接体和氧化还原活性连接体对二氧化碳的降解的协同作用.
- 阐明这些复合体中控制CO2电减和H2演变的动力机制.
- 建立设计先进分子电催化剂的一般原则.
主要方法:
- 合成含有N-异环碳素 (NHC) 和特皮里丁 (tpy) 配体的异构复合物.
- 化学和电化学运动的比较研究.
- 连接物解离的动态分析和机械学研究.
主要成果:
- 与皮科林配体相比,NHC配体显著加速化物解离 (1000倍更快).
- 氧化还原活性联体促进了降低性CO分离,速度常数跨越12个数量级.
- 复合物与NHC转移到活性部位有效催化二氧化碳转化为二氧化碳.
结论:
- 强的转变效应 (NHC) 和氧化还原活性 (tpy) 配体的组合对于在中度过电位时快速的二氧化碳电还原至关重要.
- 连接体几何学和电荷对催化性能和反应途径有重要影响.
- 这些发现为分子电催化剂的合理设计提供了有价值的机械见解.
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