A stable porphyrinic metal–organic framework pore-functionalized by high-density carboxylic groups for proton conduction

Abstract

A new porphyrinic metal–organic framework (MOF), [Co(DCDPP)]·5H₂O, was designed and constructed by using a bifunctional ligand, 5,15-di(4-carboxylphenyl)-10,20-di(4-pyridyl)porphyrin (H₂DCDPP). This MOF features a three-dimensional framework structure with open channels, surrounded by high-density non-coordinating carboxylic groups, and exhibits a high proton conductivity of 3.9 × 10⁻² S cm⁻¹ at 80 °C and 97% relative humidity, higher than most conductive MOFs. Moreover, it also shows excellent stability in boiling water and cyclic proton conduction.