A Microporous Zirconium Metal-Organic Framework Based on trans-Aconitic Acid for Selective Carbon Dioxide Adsorption

Abstract

The discovery of naturally occurring linker-based zirconium MOFs with permanent porosity and accessible functional groups remains a challenge. Using trans-aconitic acid to assemble with Zr6 oxoclusters under green and scalable conditions, a novel microporous Zr-aconitate framework has been prepared successfully with a high space-time yield. This MOF is isostructural to the previously reported Zr-fumarate, however with a smaller pore size and an abundant concentration of free acetic acid functional groups. This MOF shows an excellent chemical stability under various conditions, including boiling water, concentrated acids, and basic solution with pH below 12. Furthermore, this compound not only shows a higher carbon dioxide uptake compared to the Zr-fumarate analogue but also exhibits a notably enhanced adsorptive selectivity for carbon dioxide over nitrogen in the entire pressure range.