Progress in Cu-based electrocatalysts for electrochemical CO2 reduction to C2+ products

Abstract

Electrochemical carbon dioxide reduction reaction (CO₂RR) into multi-carbon (C₂₊) products with higher energy density and wider applicability is a promising route for CO₂ utilization. However, the selectivity and yield of C₂₊ products remain challenging owing to the involvement of multiple electron transfer and the competing reaction, i.e., the hydrogen evolution reaction (HER). Here, we review recent progress in Cu-based electrocatalysts for CO₂RR to C₂₊ products. First, possible reaction pathways for CO₂RR to C₂₊ products are discussed, focusing on the mechanism of C–C bond formation. Then, strategies of Cu-based electrocatalysts for CO₂RR into C₂₊ products are summarized, the key of which is the modulation in C–C coupling of intermediates, leading to different product selectivities. In addition, the progress in in situ techniques for the elucidation of the mechanism is underlined, which is conducive to the precise design of efficient electrocatalysts. The outlooks along with current challenges are finally proposed for the future development of C₂₊-oriented CO₂RR systems.