A hydrolytically stable MOF material, named KAUST-7’, was derived from a structural phase change of KAUST-7 upon exposure to conditions akin to protonic conduction (363 K / 95% Relative Humidity). KAUST 7’ exhibited a superprotonic conductivity as evidenced by the impedance spectroscopic measurement revealing an exceptional conductivity up to 2.0 x 10-2 S.cm-1 at 363 K and under 95% RH, a performance maintained over 7 days. Ab initio Molecular Dynamics simulations suggested that the water-mediated proton transport mechanism is governed by water assisted reorganization of the H-bond network involving the pending fluorine moieties in KAUST-7’ and the guest water molecules. The notable level of performances combined with a very good hydrolytic stability positions KAUST-7’ as a prospective proton-exchange membrane alternative to the commercial benchmark Nafion. Furthermore, the remarkable RH sensitivity of KAUST-7’ conductivity, substantially higher than previously reported MOFs, offers great opportunities for deployment as a humidity sensor.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): CPF 2910
Acknowledgements: The research leading to these results has received funding from the King Abdullah University of Science and Technology (KAUST) under Center Partnership Fund Program (CPF 2910). P.G.M. thanks the National Counsel of Technological and Scientific Development (CNPQ) for the scholarship. G.M. thanks the Institut Universitaire de France for its support. The authors declare no competing financial interest.