A Review of Metal‐ and Metal‐Oxide‐Based Heterogeneous Catalysts for Electroreduction of Carbon Dioxide

Abstract Capping and, eventually, reducing the atmospheric levels of greenhouse gases such as CO₂ is an urgent priority, and a focus of multidisciplinary efforts. Among other techniques, advanced technologies for CO₂ capture and conversion are highly desirable to limit CO₂ emissions. Electrochemical reduction of CO₂, using off‐peak renewable electricity, to value‐added chemicals and fuels has attracted extensive research interest. A main effort is directed toward the development of efficient, selective, and robust electrocatalysts to promote CO₂ reduction, due to its sluggish reaction kinetics. Here, recent investigations and achievements in the design of metal‐ and metal‐oxide‐based heterogeneous catalysts are reviewed in terms of catalytic activity, selectivity, stability, and mechanism. A classification of heterogeneous CO₂ catalysts is presented based on the main products of electrochemical reduction of CO₂, including HCOOH, CO, C₂H₄, CH₃OH, and C₃H₈O. The key catalysts' properties favoring the production of specific chemical products from the CO₂ reduction reaction are critically discussed. The challenges for achieving superior CO₂ reduction electrocatalysts are discussed providing future research directions for their design and development.