Year: 2026
Type: preprint
Abstract: Despite growing interest in metal-organic frameworks (MOFs for protonconductivity applications, monovalent-cation-based MOFs remain comparatively underexplored due to the weaker coordination interactions typically associated with these systems. In this work, we report GR-MOF-28, a novel potassium-based naphthalene tetracarboxylate framework synthesized under mild aqueous conditions at room temperature. Structurally, GR-MOF-28 consists of K2O10 dioctahedra interconnected through tetracarboxylate ligands and coordinated water molecules, generating a confined hydrogen-bond network along the crystallographic channels. The material exhibits proton conductivity values up to 4.3·10-2 S·cm-1 under high relative humidity conditions, placing it among the highest-performing K-based MOFs reported to date. Combined electrochemical impedance spectroscopy and molecular simulations support a water-mediated Grotthusstype proton transport mechanism through the confined hydrogen-bond network. In addition, GR-MOF-28 can be incorporated into a conductive polymer matrix without loss of proton transport properties. These results highlight the potential of underexplored K-based coordination frameworks as proton-conducting materials.
Source: ChemRxiv
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7211957930