Synergistic surface modification of Cu with schiff-base networks for high selectivity and durability in CO2-to-C2H4 electroreduction

The electrocatalytic CO2 reduction reaction (e-CO2RR) on Cu-based catalysts has been extensively studied; however, achieving high selectivity for C2+ products and long-term durability remains challenging. Here, we introduce a straightforward approach that enhances both C2H4 selectivity and catalyst durability by incorporating a nitrogen-rich Schiff-base Network (SNW), leveraging a synergistic interaction between Cu and SNW. Notably, Cu cubes with SNW, predominantly exposing the Cu(200) facet, achieve a Faradaic Efficiency (FE) of 71.2% for C2H4 at a current density of 265 mA cm−2, which not only exceeds tetrahedral and spherical Cu with or without SNW, but also ranks competitively among state‑of‑the‑art Cu-based catalysts reported to date. Theoretical calculations suggest that the presence of SNW on Cu facilitates the *CO-*CHO coupling and/or the C2H4 desorption, thereby enhancing C2H4 formation. Furthermore, the Cu(200)-SNW surface exhibits optimized Gibbs free energies for the reaction steps compared to bare Cu and other SNW-modified Cu surfaces, which rationalizes the experimental observations. In situ electron microscopy further suggests that SNW confers durability by stabilizing Cu facets and preventing corrosion and dissolution under reaction conditions. Cu catalysts show promise for converting CO2 into valuable products, but achieving high selectivity and long-term stability remains challenging. Here, modifying Cu cubes with a nitrogen-rich organic network enables a Faradaic Efficiency of 71.2% for C2H4 production with greatly enhanced durability.