An Electrically Conducting Three-Dimensional Iron-Catecholate Porous Framework

Angew Chem Int Ed Engl. 2021 Aug 9;60(33):18065-18072. doi: 10.1002/anie.202102670. Epub 2021 Jul 1.

Abstract

We report the synthesis of a unique cubic metal-organic framework (MOF), Fe-HHTP-MOF, comprising hexahydroxytriphenylene (HHTP) supertetrahedral units and FeIII ions, arranged in a diamond topology. The MOF is synthesized under solvothermal conditions, yielding a highly crystalline, deep black powder, with crystallites of 300-500 nm size and tetrahedral morphology. Nitrogen sorption analysis indicates a highly porous material with a surface area exceeding 1400 m2 g-1 . Furthermore, Fe-HHTP-MOF shows broadband absorption from 475 up to 1900 nm with excellent absorption capability of 98.5 % of the incoming light over the visible spectral region. Electrical conductivity measurements of pressed pellets reveal a high intrinsic electrical conductivity of up to 10-3 S cm-1 . Quantum mechanical calculations predict Fe-HHTP-MOF to be an efficient electron conductor, exhibiting continuous charge-carrier pathways throughout the structure.

Keywords: electrical conductivity; iron-catecholate; metal-organic frameworks; porosity; three-dimensional framework.