Zhang Gui-Rong, Straub Sascha-Dominic, Shen Liu-Liu, Hermans Yannick, Schmatz Patrick, Reichert Andreas M, Hofmann Jan P, Katsounaros Ioannis, Etzold Bastian J M
Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Technical University of Darmstadt, Alarich-Weiss-Str. 8, 64287, Darmstadt, Germany.
Surface Science Laboratory, Department of Materials and Earth Sciences, Technical University of Darmstadt, Otto-Berndt-Str. 3, 64287, Darmstadt, Germany.
Angew Chem Int Ed Engl. 2020 Oct 5;59(41):18095-18102. doi: 10.1002/anie.202009498. Epub 2020 Sep 3.
The key to fully leveraging the potential of the electrochemical CO reduction reaction (CO2RR) to achieve a sustainable solar-power-based economy is the development of high-performance electrocatalysts. The development process relies heavily on trial and error methods due to poor mechanistic understanding of the reaction. Demonstrated here is that ionic liquids (ILs) can be employed as a chemical trapping agent to probe CO2RR mechanistic pathways. This method is implemented by introducing a small amount of an IL ([BMIm][NTf ]) to a copper foam catalyst, on which a wide range of CO2RR products, including formate, CO, alcohols, and hydrocarbons, can be produced. The IL can selectively suppress the formation of ethylene, ethanol and n-propanol while having little impact on others. Thus, reaction networks leading to various products can be disentangled. The results shed new light on the mechanistic understanding of the CO2RR, and provide guidelines for modulating the CO2RR properties. Chemical trapping using an IL adds to the toolbox to deduce the mechanistic understanding of electrocatalysis and could be applied to other reactions as well.
充分利用电化学二氧化碳还原反应（CO2RR）的潜力以实现可持续的太阳能经济的关键在于开发高性能的电催化剂。由于对该反应的机理理解不足，开发过程严重依赖试错法。本文证明离子液体（ILs）可作为化学捕获剂来探测CO2RR的机理途径。该方法通过将少量离子液体（[BMIm][NTf ]）引入泡沫铜催化剂来实现，在该催化剂上可产生包括甲酸盐、一氧化碳、醇类和碳氢化合物在内的多种CO2RR产物。离子液体可以选择性地抑制乙烯、乙醇和正丙醇的生成，而对其他产物影响很小。因此，可以解开导致各种产物的反应网络。这些结果为CO2RR的机理理解提供了新的思路，并为调节CO2RR性能提供了指导。使用离子液体进行化学捕获为推断电催化的机理理解增添了一种工具，并且也可应用于其他反应。
