Electrochemical CO2 Reduction on Cu: Synthesis-Controlled Structure Preference and Selectivity

Abstract

The electrochemical CO₂ reduction reaction (ECO₂ RR) on Cu catalysts affords high-value-added products and is therefore of great practical significance. The outcome and kinetics of ECO₂ RR remain insufficient, requiring essentially the optimized structure design for the employed Cu catalyst, and also the fine synthesis controls. Herein, synthesis-controlled structure preferences and the modulation of intermediate's interactions are considered to provide synthesis-related insights on the design of Cu catalysts for selective ECO₂ RR. First, the origin of ECO₂ RR intermediate-dominated selectivity is described. Advanced structural engineering approaches, involving alloy/compound formation, doping/defect introduction, and the use of specific crystal facets/amorphization, heterostructures, single-atom catalysts, surface modification, and nano-/microstructures, are then reviewed. In particular, these structural engineering approaches are discussed in association with diversified synthesis controls, and the modulation of intermediate generation, adsorption, reaction, and additional effects. The results pertaining to synthetic methodology-controlled structural preferences and the correspondingly motivated selectivity are further summarized. Finally, the current opportunities and challenges of Cu catalyst fabrication for highly selective ECO₂ RR are discussed.

Keywords: catalysis; copper; electrochemical CO2 Reduction; structural engineering; synthesis.