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Sodium-coupled electron transfer reactivity of metal-organic frameworks containing titanium clusters: the importance of cations in redox chemistry.

ABSTRACT: Stoichiometric reduction reactions of two metal-organic frameworks (MOFs) by the solution reagents (M = Cr, Co) are described. The two MOFs contain clusters with Ti₈O₈ rings: Ti₈O₈(OH)₄(bdc)₆; bdc = terephthalate (MIL-125) and Ti₈O₈(OH)₄(bdc-NH₂)₆; bdc-NH₂ = 2-aminoterephthalate (NH₂-MIL-125). The stoichiometry of the redox reactions was probed using solution NMR methods. The extent of reduction is greatly enhanced by the presence of Na⁺, which is incorporated into the bulk of the material. The roughly 1 : 1 stoichiometry of electrons and cations indicates that the storage of e^- in the MOF is tightly coupled to a cation within the architecture, for charge balance.

SUBMITTER: Saouma CT

PROVIDER: S-EPMC6354900 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Sodium-coupled electron transfer reactivity of metal-organic frameworks containing titanium clusters: the importance of cations in redox chemistry.

Saouma Caroline T CT Tsou Chih-Chin CC Richard Sarah S Ameloot Rob R Vermoortele Frederik F Smolders Simon S Bueken Bart B DiPasquale Antonio G AG Kaminsky Werner W Valdez Carolyn N CN De Vos Dirk E DE Mayer James M JM

Chemical science 20181119 5

Stoichiometric reduction reactions of two metal-organic frameworks (MOFs) by the solution reagents (M = Cr, Co) are described. The two MOFs contain clusters with Ti8O8 rings: Ti8O8(OH)4(bdc)6; bdc = terephthalate (MIL-125) and Ti8O8(OH)4(bdc-NH2)6; bdc-NH2 = 2-aminoterephthalate (NH2-MIL-125). The stoichiometry of the redox reactions was probed using solu ...[more]

PMID: 30809347

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