Recent advances in upgrading CO2 to C3+ products via electrochemical and complementary engineering

Abstract

Upgrading CO₂ to various carbon-containing products through renewable electrochemical routes offers a promising solution to achieve a “Net Zero” and circular economy. Multicarbon C₃₊ products are especially energy-rich and economically valuable. However, due to the diverse possibilities of C–C coupling and the complexities of reaction pathways, the efficient and selective electrochemical reduction of CO₂ to C₃₊ products remains a tremendous challenge. Summarizing the latest advances in generating C₃₊ products from CO₂, this review focuses on both key material development and process design in electrochemical and complementary engineering approaches. For the methodologies involving only electrochemical reactions, we categorize them based on the catalysts adopted, summarizing the specific design strategies and mechanistic understandings of copper and non-copper catalysts, respectively. To further improve the efficiency of C₃₊ synthesis, the concept of “electrochemical + X” is introduced. “X” herein refers to a complementary sector to direct CO₂ electrolysis, encompassing the homogeneous non-electrocatalytic reactions in a one-pot electrochemical process and the sequential thermochemical or biological processes after electrochemical CO₂ conversion. Lastly, we discuss the challenges of pure electrochemical as well as “electrochemical + X” approaches and outline promising future directions. We believe that this review contains a comprehensive summary of the means to optimize for C₃₊ compounds, and can motivate researchers to develop innovative strategies to further enhance C₃₊ production efficiency, paving the way towards the ultimate renewable-driven chemical industries.