Insight into dynamic and steady-state active sites for nitrogen activation to ammonia by cobalt-based catalyst.

ABSTRACT: The industrial synthesis of ammonia (NH₃) using iron-based Haber-Bosch catalyst requires harsh reaction conditions. Developing advanced catalysts that perform well at mild conditions (<400 °C, <2 MPa) for industrial application is a long-term goal. Here we report a Co-N-C catalyst with high NH₃ synthesis rate that simultaneously exhibits dynamic and steady-state active sites. Our studies demonstrate that the atomically dispersed cobalt weakly coordinated with pyridine N reacts with surface H₂ to produce NH₃ via a chemical looping pathway. Pyrrolic N serves as an anchor to stabilize the single cobalt atom in the form of Co₁-N_3.5 that facilitates N₂ adsorption and step-by-step hydrogenation of N₂ to *HNNH

SUBMITTER: Wang X 

PROVIDER: S-EPMC6994663 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature