Coordination-Induced N-H Bond Splitting of Ammonia and Primary Amine of CuI -MOFs

Kuan Gao; Chao Huang; Yan Qiao; Shasha Wang; Jie Wu; Hongwei Hou

doi:10.1002/chem.202100781

Coordination-Induced N-H Bond Splitting of Ammonia and Primary Amine of Cu^I -MOFs

Chemistry. 2021 Jul 2;27(37):9499-9502. doi: 10.1002/chem.202100781. Epub 2021 Jun 1.

Authors

Kuan Gao¹, Chao Huang², Yan Qiao³, Shasha Wang¹, Jie Wu¹, Hongwei Hou¹

Affiliations

¹ Green Catalysis Center and College of Chemistry, Zhengzhou University, 45001, Zhengzhou, P. R. China.
² Center for Advanced Materials Research, Henan Key Laboratory of Functional Salt Materials, Zhongyuan University of Technology, 45001, Zhengzhou, P. R. China.
³ Pathophysiology Department, Basic Medical College of Zhengzhou University, 45001, Zhengzhou, P. R. China.

PMID: 33998739
DOI: 10.1002/chem.202100781

Abstract

We report a porous three-dimensional anionic tetrazolium based Cu^I -MOF 1, which is capable of cleaving the N-H bond of ammonia and primary amine, as well as the O-H bond of H₂ O along with spontaneous H₂ evolution. In the gas-solid phase reaction of 1 with ammonia and water vapor, Cu^I -MOF 1 was gradually oxidized to NH₂ -Cu^II -MOF and OH-Cu^II -MOF, through single-crystal-to-single-crystal (SCSC) structural transformations, which was confirmed by XPS, PXRD and X-ray single-crystal diffraction. Density functional theory (DFT) demonstrated that Cu^I -MOF could lower N-H bond dissociation free energy of ammonia through coordination-induced bond weakening and promote H₂ evolution by the reduction potential of 1. To our knowledge, this is the first example of MOFs that activate ammonia and amine in gas-solid manner.

Keywords: SC to SC; coordination-induced bond weakening; gas-solid phase; oxidation of NH3.

Abstract

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