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

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.

Microbial electrosynthesis of valuable chemicals from the reduction of CO2: a review.

The present energy demand of the world is increasing but the fossil fuels are gradually depleting. As a result, the need for alternative fuels and energy sources is growing. Fuel cells could be one alternative to address the challenge. The fuel cell can convert CO2 to value-added chemicals. The potential of bio-fuel cells, specifically enzymatic fuel cells and microbial fuel cells, and the importance of immobilization technology in bio-fuel cells are highlighted. The review paper also includes a detailed explanation of the microbial electrosynthesis system to reduce CO2 and the value-added products during microbial electrosynthesis. Future research in bio-electrochemical synthesis for CO2 conversion is expected to prioritize enhancing biocatalyst efficiency, refining reactor design, exploring novel electrode materials, understanding microbial interactions, integrating renewable energy sources, and investigating electrochemical processes for carbon capture and selective CO2 reduction. The challenges and perspectives of bio-electrochemical systems in the application of CO2 conversion are also discussed. Overall, this review paper provides valuable insights into the latest developments and criteria for effective research and implementation in bio-fuel cells, immobilization technology, and microbial electro-synthesis systems.