Improving the selectivity of electrochemical CO2 reduction to multicarbon chemicals through microenvironment engineering

Electrochemical carbon dioxide reduction reaction (eCO₂RR) is a promising approach to reduce the concentration of CO₂ in the atmosphere and produce value-added chemicals. Due to the high stability of CO₂ and the complex reaction pathways, the selectivity and reaction rate of converting CO₂ into high-value chemicals, especially multicarbon products, remain unsatisfactory for viable commercial applications. In conjunction with developing catalysts with high intrinsic activity and selectivity, engineering the microenvironment to which the catalysts are exposed has become a versatile and effective means to steer the reaction pathway toward desirable C₂₊ products with high selectivity and at a practically viable current density. This review provides an overview of recent advancements in steering eCO₂RR toward C₂₊ on Cu-based catalysts through microenvironment engineering in the past two years. Selective examples are used to illustrate the efficacy of each microenvironment engineering approach. Perspectives on future research directions are also provided.