Boosting Selective Nitrogen Reduction via Geometric Coordination Engineering on Single-Tungsten-Atom Catalysts.

Atomic interface regulation that can efficiently optimize the performance of single-atom catalysts (SACs) is a worthwhile research topic. The challenge lies in deeply understanding the structure-properties correlation based on control of the coordination chemistry of individual atoms. Herein, a new kind of W SACs with oxygen and nitrogen coordination (W-NO/NC) and a high metal loading over 10 wt% is facilely prepared by introducing an oxygen-bridged [WO4 ] tetrahedron. The local structure and coordination environment of the W SACs are confirmed by high-angle annular dark-field scanning transmission electron microscopy, X-ray photoelectron spectroscopy, and extended X-ray absorption fine structure. The catalyst shows excellent selectivity and activity for the electrochemical nitrogen reduction reaction (NRR). Density functional theory calculation reveals that unique electronic structures of the N and O dual-coordinated W sites optimize the binding energy of the NRR intermediate, resulting in facilitating the electrocatalytic NRR. This work opens an avenue toward exploring the correlation between coordination structure and properties.