Design of Heteroatomic Active Sites for Electrochemical CO x Reduction Toward Multicarbon Products

The electrochemical CO 2 and CO reduction (CO x RR) to value‐added multicarbon (C2+) products offers a promising route for sustainable carbon recycling and renewable fuel generation. Although Cu catalysts exhibit unique activity, these single‐metal sites are constrained by linear scaling relations of intermediate adsorption energies, which limits further improvements in selectivity and energy efficiency. Introducing heteroatoms to regulate active‐site coordination provides an effective approach to transcend these limitations. This review describes recent advances in the theoretical design, controllable fabrication, and mechanistic investigation of heteroatomic active sites for CO x RR toward C2+ products. Theoretical identification for high‐performance sites through descriptor‐based modeling, data‐driven screening, and dynamic simulations is first discussed. Then, the precision synthesis strategies for constructing atomically dispersed, long‐range‐ordered, and interfacial‐confined heteroatomic structures are systematically summarized. Subsequently, mechanistic insights into the promoting effect of heteroatoms, driven by synergistic electronic and geometric modulation, are highlighted, followed by an analysis of future research directions and the key challenges for the industrial implementation of heteroatomic catalysts for CO x RR. This review provides an integrated perspective linking active‐site design to catalytic performance, offering guidance for the development of next‐generation heteroatomic electrocatalysts for efficient CO x RR toward the sustainable production of high‐value chemicals.