Transforming CO Poisoning into a Critical Step for Electrocatalytic C─N Coupling to Urea in a Carbon‐Dot‐Dominated Nanoreactor

Modern catalysis science has traditionally viewed carbon monoxide (CO) poisoning negatively due to its detrimental effects, such as the deactivation of metal sites. Here, we demonstrate a transformative approach by converting CO poisoning into a beneficial strategy to achieve high activity and selectivity in urea electrosynthesis. We designed a multiscale and multisite nanoreactor composed of copper–carbon dots (Cu‐CDs) and bornite (Cu 5 FeS 4 ), which exploits CO‐poisoned iron sites as anchors to facilitate efficient multi‐species integration. This nanoreactor configuration delivers an unprecedented C urea ‐ selectivity of 100%, a high urea yield rate of 1131.84 µg h −1 mg cat −1 and a Faradaic efficiency of 42.35% at an ultra‐low potential. Consequently, the catalyst achieves exceptional dual benefits of a high yield rate and low energy consumption of 31.18 kWh kg urea −1 , outperforming all previously reported earth‐abundant electrocatalysts. Mechanistic studies and theoretical calculations reveal that the strong interaction between Fe and *CO, coupled with spatially separated yet adjacent Fe, Cu 1 , and Cu 2 sites, enables stepwise conversion from *CO to *CONH 2 and subsequently to *CO(NH 2 ) 2 within the nano‐confined space dominated by Cu‐CDs. This work provides a groundbreaking catalyst design strategy by effectively harnessing CO poisoning for enhanced electrocatalytic performance.