Circumventing Scaling Relations via Gradient Orbital Coupling Promotes Ammonia Electrosynthesis on Cobalt Catalyst

Highly efficient electrocatalytic nitrate reduction to ammonia (NH₃) relies on the balanced activation of various substrates including nitrate and water, but is currently hindered by the inherent scaling relations governing the adsorption of key reaction intermediates, such as *NO and *H. Herein, we develop a strategy to circumvent these limitations by introducing f-d-p gradient orbital coupling in cobalt oxide (Co₃O₄) through Ce doping. Density functional theory calculations indicate that the lattice strain triggered by the dopant redistributes electron density at the Co and O sites, thereby modulating the adsorption strengths of *NO and *H, which favors the production of NH₃ while suppressing hydrogen evolution reaction. It exhibits a faradaic efficiency of 97.8% and a high yield rate of 3423.0 µg h^-1 cm^-2 under alkaline conditions. Furthermore, Ce/Co₃O₄ catalyst shows robust performance over a wide range of nitrate concentrations (from 5 to 200 mM) and excellent cycling stability. Our findings also suggest that the gradient orbital coupling approach can be extended to other lanthanide dopants (e.g., Pr and Nd), offering a broadly applicable platform to break scaling relations and improve NO₃ ^--to-NH₃ activity on cobalt catalysts.