Redox-tunable Lewis bases for electrochemical carbon dioxide capture
Redox-tunable Lewis bases for electrochemical carbon dioxide capture
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DOI：
10.1038/s41560-022-01137-z
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发表时间：
2022-10-13
期刊：
影响因子：
56.7
通讯作者：
Liu, Yayuan
中科院分区：
文献类型：
--
作者：
Li, Xing;Zhao, Xunhua;Liu, Yayuan
碳捕获的电化学方法具有在环境条件下操作和模块化设计的优点，但仍然需要改进的吸附剂分子。在这里，作者提出了一个氧化还原可调的刘易斯碱库，阐明了分子设计准则，以调整吸附剂的性能。碳捕获被认为是减缓气候变化的关键手段。然而，利用sp（3）胺的常规湿化学洗涤遭受高能耗、腐蚀和吸附剂降解，从而促使人们寻求更有效的二氧化碳分离策略。在这里，我们展示了一个库的氧化还原可调刘易斯碱与sp（2）-氮中心，可以可逆地捕获和释放二氧化碳通过电化学循环。通过实验和计算相结合的方法阐明了碳捕获过程的机制。我们表明，这些刘易斯碱吸附剂的性能可以通过分子设计和电解质工程微调。此外，我们确定了一种双官能偶氮吡啶碱，它有望用于电化学介导的碳捕获，在15%二氧化碳和5%氧气的流动系统中循环时表现出>85%的容量利用效率。这项工作拓宽了氧化还原活性二氧化碳吸附剂的结构范围，并提供了在电化学条件下具有可调碱性的分子的设计指南。
Electrochemical approaches to carbon capture have the advantages of operation under ambient conditions and modular design, but improved sorbent molecules are still needed. Here the authors present a library of redox-tunable Lewis bases, shedding light on molecular design guidelines to tune sorbent properties.Carbon capture is considered a critical means for climate change mitigation. However, conventional wet chemical scrubbing utilizing sp(3) amines suffers from high energy consumption, corrosion and sorbent degradation, motivating the search for more efficient carbon dioxide separation strategies. Here, we demonstrate a library of redox-tunable Lewis bases with sp(2)-nitrogen centres that can reversibly capture and release carbon dioxide through an electrochemical cycle. The mechanism of the carbon capture process is elucidated via a combined experimental and computational approach. We show that the properties of these Lewis base sorbents can be fine-tuned via molecular design and electrolyte engineering. Moreover, we identify a bifunctional azopyridine base that holds promise for electrochemically mediated carbon capture, exhibiting >85% capacity utilization efficiency over cycling in a flow system under 15% carbon dioxide with 5% oxygen. This work broadens the structural scope of redox-active carbon dioxide sorbents and provides design guidelines on molecules with tunable basicity under electrochemical conditions.