The massive emission of excess greenhouse gases (mainly CO 2) have an irreversible impact on the Earth's ecology. Electrocatalytic CO 2 reduction (ECR), a technique that utilizes renewable energy sources to create highly reduced chemicals ( e.g. C 2H 4, C 2H 5OH), has attracted significant attention in the science community. Cu-based catalysts have emerged as promising candidates for ECR, particularly in producing multi-carbon products that hold substantial value in modern industries. The formation of multi-carbon products involves a range of transient intermediates, the behaviour of which critically influences the reaction pathway and product distribution. Consequently, achieving desirable products necessitates precise regulation of these intermediates. This review explores state-of-the-art designs of Cu-based catalysts, classified into three categories based on the different prospects of the intermediates' modulation: heteroatom doping, morphological structure engineering, and local catalytic environment engineering. These catalyst designs enable efficient multi-carbon generation in ECR by effectively modulating reaction intermediates.
Product distribution during electrocatalytic CO 2 reduction is closely related to the behaviour of reaction intermediates. Morphological and microenvironmental engineering of Cu-based catalysts can regulate the reaction tendency of intermediates, enabling target products to be selectively obtained.