Electrolytic cell design for electrochemical CO2 reduction

Transmute CO2 to value-added chemical products by electrochemical reduction is a potential candidate and a highly providential route to mitigate CO2 levels in atmosphere and meet the energy and global warming crisis. Recent reported studies have focused on advancement of novel electro-catalysts with outstanding performance, but unfortunately, little attention has been paid to the influence of reactor design. In this contribution, we for the first time comprehensively review all types of electrolytic cells reported in literatures and compare their features, advantages and disadvantages for CO2 electro-reduction. To date, H-type cell is still the well-known typical reactor for CO2RR, typically for screening electro-catalysts. Based on H-type cell, a similar modified sandwich-type cell is designed to reduce system resistance. However, for industrialization, the flow cell in which the reactants and products are continuously transferred to and away from the electrodes, need further advancement because of its efficient mass transfer efficiency. Besides, the DEMS cell is an effective way to detect products efficiently in real time and analyze reaction process, which is useful for seeking reaction mechanism. The perspectives and challenges for the development of electrochemical cells are also addressed. We hopeful, this review should provide researchers with a clearer understanding of reactor selection, and impart important, timely and valuable insights into the design of advance electrolytic cells and its practical applications for CO2 reduction.