Electrochemical conversion of CO₂ to fuels: tuning of the reaction zone using suitable functional groups in a solid...

The electrochemical reduction of gaseous CO2 is studied for the first time using sterically hindered bulky quaternary ammonium ions in a solid polymer matrix at room temperature and atmospheric pressure in a developed electrochemical reactor. Some new insights are found, leading to an effective reaction process. It is found that the reaction zone can be tuned to a great extent with the help of fixed functional groups attached to the solid polymer. To illustrate the concept, solid polymer electrolytes with the same backbone and different fixed functional groups are synthesized. It is found that only a change to the functional group in the membrane is needed to dramatically change the efficiency and selectivity of the reaction products. Suitable groups may increase the mass transfer of CO2 at the reaction interface and help as a co-catalyst. This work may open a new approach for the development of next generation processes for gaseous CO2 electroreduction to fuels, which is a present need.