Synthesis of micro–mesoporous CPO-27-Mg@KIT-6 composites and their test in CO2 adsorption

Abstract

In this work, we present the preparation of hybrid materials constituted by a Metal Organic Framework (type CPO-27-Mg) and a mesoporous silica (type KIT-6) which were successfully assembled through an in situ hydrothermal method. The composites were characterised by powder X-ray diffraction (PXRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), microscopic techniques (SEM and TEM), N₂ adsorption–desorption isotherms at 77 K and CO₂ adsorption at 273 K; these techniques confirmed the obtaining of hybrid materials and not simple physical mixtures. Finally, the hybrid materials were tested in the CO₂ adsorption at different temperatures and from 0–10 bar of pressure, where the exposure to high relative humidity were also monitored. The CPO-27-Mg@KIT-6 (1 : 1) and (2 : 1) composites exhibited interesting values of CO₂ adsorption capacity, compared with those reported in the literature. Therefore, this study opens new pathways for designing porous structured MOF-based materials with advanced gas separation performance.