A Series of Metal-Organic Frameworks for Selective CO2 Capture and Catalytic Oxidative Carboxylation of Olefins

Abstract

Three new lanthanide-based metal-organic frameworks (Ln-MOFs), namely MOF-590, -591, and -592 constructed from a tetratopic linker, benzoimidephenanthroline tetracarboxylic acid (H₄BIPA-TC), were synthesized under solvothermal conditions and fully characterized. All of the new MOFs exhibit three-dimensional frameworks, which adopt unprecedented topologies in MOF field. Gas adsorption measurements of MOF-591 and -592 revealed good adsorption of CO₂ (low pressure, at room temperature) and moderate CO₂ selectivity over N₂ and CH₄. Consequently, breakthrough experiments illustrated the separation of CO₂ from binary mixture of CO₂ and N₂ with the use of MOF-592. Accordingly, MOF-592 revealed the selective CO₂ capture effectively without any loss in performance after three cycles. Moreover, MOF-590, -591, and -592 showed to be catalytically active in the oxidative carboxylation of styrene and CO₂ for a one-pot synthesis of styrene carbonate under mild conditions (1 atm CO₂, 80 °C, and without solvent). Among the new materials, MOF-590 revealed a remarkable efficiency with exceptional conversion (96%), selectivity (95%), and yield (91%).