加拿大多伦多大学教授Edward H. Sargent团队报道了强酸性条件下CO2电解制取多碳产物。相关研究成果发表在2021年6月4日出版的《科学》。

二氧化碳电还原（CO₂R）是一种很有前途的将碳排放转化为有价值的化学物质和燃料的方法。然而，生产对于多碳产品减少的输入二氧化碳的分数通常非常低，<2%；在碱性和中性反应器中，含氢氧化物的平衡反应生成碳酸盐。酸性电解质可以克服这一限制，但迄今为止，在这些条件下，析氢一直占主导地位。

研究人员报道了在电化学活性中心附近富集钾离子可以加速CO2的活化，从而在酸中产生高效还原CO₂。研究人员在pH<1的铜上，电流密度为1.2安培/平方厘米，全电池电压为4.2伏的条件下，实现了CO₂还原，单次CO₂利用率为77%，包括向多碳产物（乙烯、乙醇和1-丙醇）的转化效率为50%。

附：英文原文

Title: CO2 electrolysis to multicarbon products in strong acid

Author: Jianan Erick Huang, Fengwang Li, Adnan Ozden, Armin Sedighian Rasouli, F. Pelayo García de Arquer, Shijie Liu, Shuzhen Zhang, Mingchuan Luo, Xue Wang, Yanwei Lum, Yi Xu, Koen Bertens, Rui Kai Miao, Cao-Thang Dinh, David Sinton, Edward H. Sargent

Issue&Volume: 2021/06/04

Abstract: Carbon dioxide electroreduction (CO2R) is being actively studied as a promising route to convert carbon emissions to valuable chemicals and fuels. However, the fraction of input CO2 that is productively reduced has typically been very low, <2% for multicarbon products; the balance reacts with hydroxide to form carbonate in both alkaline and neutral reactors. Acidic electrolytes would overcome this limitation, but hydrogen evolution has hitherto dominated under those conditions. We report that concentrating potassium cations in the vicinity of electrochemically active sites accelerates CO2 activation to enable efficient CO2R in acid. We achieve CO2R on copper at pH <1 with a single-pass CO2 utilization of 77%, including a conversion efficiency of 50% toward multicarbon products (ethylene, ethanol, and 1-propanol) at a current density of 1.2 amperes per square centimeter and a full-cell voltage of 4.2 volts.

DOI: 10.1126/science.abg6582

Source: https://science.sciencemag.org/content/372/6546/1074