Multifunctionality of weak ferromagnetic porphyrin-based MOFs: selective adsorption in the liquid and gas phase

Abstract

With the endless possibilities of metal organic framework design, the quest for new multifunctional materials with desirable properties is still ongoing. At the environmental level, their development poses a promising industrial alternative for the management of aqueous pollutants and for storage and separation of gases. In this context, the recently reported porphyrinic framework 1, [Ni₅(H₂TCPP)₂O(H₂O)₄]·nS (where TCPP is meso-tetra(4-carboxyphenyl)porphyrin and S is the solvent), is investigated through a fundamental study of its thermal and magnetic properties, together with its potential as an adsorbent for pollutants in the liquid and gas phase. Sorption of four organic dye solutions with different chemical features was carried out, with good affinity found towards small cationic species. In addition, a series of different gases (N₂, O₂, CO, CO₂, and C1–C4 hydrocarbons) were tested through the use of adsorption microcalorimetry in order to understand the interactions and selectivity of 1. This study affords an in-depth approach to the characterization of a new selective adsorbent for pollutants of industrial interest.