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Neutron diffraction structural study of CO₂ binding in mixed-metal CPM-200 metal-organic frameworks.

ABSTRACT: Metal-organic frameworks featuring open metal coordination sites have been widely studied for the separation of gas mixtures. For CO₂/N₂ separations, these materials have shown considerable promise. Herein, we report the characterization of a subset of the well-known PCN-250 class of frameworks upon CO₂ adsorption via powder neutron diffraction methods. Noteably, in contrast to previously reported data, they display only moderate CO₂ adsorption enthalpies, based on metal cation-CO₂ interactions. Further, we show charge balance in these materials is likely achieved via ligand vacancies rather than the presence of ?₃-OH groups in the trimetallic cluster that comprises them.

SUBMITTER: Campanella AJ

PROVIDER: S-EPMC7874966 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Neutron diffraction structural study of CO2 binding in mixed-metal CPM-200 metal-organic frameworks.

Campanella Anthony J AJ Trump Benjamin A BA Gosselin Aeri J AJ Bloch Eric D ED Brown Craig M CM

Chemical communications (Cambridge, England) 20200203 17

Metal-organic frameworks featuring open metal coordination sites have been widely studied for the separation of gas mixtures. For CO2/N2 separations, these materials have shown considerable promise. Herein, we report the characterization of a subset of the well-known PCN-250 class of frameworks upon CO2 adsorption via powder neutron diffraction methods. Noteably, in contrast to previously reported data, they display only moderate CO2 adsorption enthalp ...[more]

PMID: 32010906

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