Tunable Coordination Number in Non‐Metal‐Introduced Copper Catalysts Enables High‐Performance Electrochemical CO 2 Reduction to C 2 Products

Abstract Copper‐based catalysts occupy a central position in electrocatalytic CO 2 reduction systems due to their unparalleled capacity to drive multicarbon (C 2+ ) product formation. Nevertheless, the realization of efficient C 2+ generation remains impeded by convoluted reaction pathways and prohibitively high activation energies for C─C bond formation. Strategic modulation of copper's coordination environment emerges as an effective lever to tailor CO 2 adsorption energetics and reconfigure reaction trajectories. Here, magnetron sputtering is employed to engineer non‐metallic heteroatom‐introduced Cu catalysts with precisely tuned coordination numbers. This coordination engineering induces a marked enrichment in surface‐bound * CO intermediate density and reduces the kinetic suppression of * CO hydrogenation to * CHO via elevated transition‐state energies. Such electronic restructurin…