Modulation of Atomically Dispersed Ru Microenvironments by a Directed Etch Template Strategy for Efficient Nitrogen Fixation

The synthesis of ammonia (NH₃) via the Haber–Bosch process is energy-intensive and environmentally challenging, necessitating the development of sustainable alternatives. Herein, we report a directed etch template strategy to create atomically dispersed Ru–N₄ active sites within layered porous carbon (NC@Ru) for efficient electrochemical nitrogen reduction reaction (NRR). The removal of the MgO template results in an interconnected carbon network with hierarchical porous structures, significantly enhancing the accessibility and mass transfer of the active sites. The NC@Ru catalyst demonstrated superior NRR performance, achieving an ammonia yield rate of 196.2 μg h^–1 mg_cat.^–1 and a Faradaic efficiency of 43.8%. In situ electrochemical mass spectrometry was employed to analyze NRR kinetics, while density functional theory calculations were utilized to elucidate the NRR mechanism and identify the rate-determining step. The work introduces a novel high-performance catalyst for electrocatalytic NRR and provides a practical strategy for optimizing active-site microenvironments, laying the groundwork for future commercial applications of electrocatalytic NRR.