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Solid solution for catalytic ammonia synthesis from nitrogen and hydrogen gases at 50?°C.

ABSTRACT: The lack of efficient catalysts for ammonia synthesis from N₂ and H₂ gases at the lower temperature of ca. 50 °C has been a problem not only for the Haber-Bosch process, but also for ammonia production toward zero CO₂ emissions. Here, we report a new approach for low temperature ammonia synthesis that uses a stable electron-donating heterogeneous catalyst, cubic CaFH, a solid solution of CaF₂ and CaH₂ formed at low temperatures. The catalyst produced ammonia from N₂ and H₂ gases at 50 °C with an extremely small activation energy of 20?kJ?mol^-1, which is less than half that for conventional catalysts reported. The catalytic performance can be attributed to the weak ionic bonds between Ca²⁺ and H^- ions in the solid solution and the facile release of hydrogen atoms from H^- sites.

SUBMITTER: Hattori M

PROVIDER: S-EPMC7181780 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Solid solution for catalytic ammonia synthesis from nitrogen and hydrogen gases at 50 °C.

Hattori Masashi M Iijima Shinya S Nakao Takuya T Hosono Hideo H Hara Michikazu M

Nature communications 20200424 1

The lack of efficient catalysts for ammonia synthesis from N2 and H2 gases at the lower temperature of ca. 50 °C has been a problem not only for the Haber-Bosch process, but also for ammonia production toward zero CO2 emissions. Here, we report a new approach for low temperature ammonia synthesis that uses a stable electron-donating heterogeneous catalyst, cubic CaFH, a solid solution of CaF2 and CaH2 formed at low temperatures. The catalyst ...[more]

PMID: 32332727

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