Recent advances in application of tandem catalyst for electrocatalytic CO₂ reduction

Electrocatalytic CO₂ reduction reaction (CO₂RR) is one of the important ways to achieve the goal of CO₂ utilization and synthesizing high-value products. Electrochemical CO₂RR involves multiple electron-proton transfer steps, resulting in low yield and low selectivity. *CO is considered as the key intermediate, the process of CO₂RR can be divided into a tandem step of CO₂-to-CO and CO-to-C₂₊. To promote kinetic rate of whole reaction and improve faraday efficiency of the product, tandem catalysts are constructed. Here, the recent advances in application of tandem catalyst for electrocatalytic CO₂RR are reviewed for three aspects: (1) tandem mechanism of electrochemical CO₂RR; (2) copper-based tandem catalysts as well as other copper-free tandem catalysts for electrochemical CO₂RR; (3) challenges, opportunities and prospects of tandem catalysts for CO₂RR. This review provides a comprehensive understanding tandem electrocatalytic mechanism of tandem catalysts for CO₂RR and important guidelines for the field of electrocatalysis.