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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-N3.5 that facilitates N2 adsorption and step-by-step hydrogenation of N2 to *HNNH, *NH-NH3 and *NH2-NH4. Finally, NH3 is facilely generated via the breaking of the *NH2-NH4 bond. With the co-existence of dynamic and steady-state single atom active sites, the Co-N-C catalyst circumvents the bottleneck of N2 dissociation, making the synthesis of NH3 at mild conditions possible.

SUBMITTER: Wang X

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

REPOSITORIES: biostudies-literature

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

Wang Xiuyun X Peng Xuanbei X Chen Wei W Liu Guangyong G Zheng Anmin A Zheng Lirong L Ni Jun J Au Chak-Tong CT Jiang Lilong L

Nature communications 20200131 1

The industrial synthesis of ammonia (NH<sub>3</sub>) 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 NH<sub>3</sub> synthesis rate that simultaneously exhibits dynamic and steady-state active sites. Our studies demonstrate that the atomically dispersed cobalt weakly coordinated with pyridine N rea ...[more]

PMID: 32005833

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

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

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