A stable dual-function lanthanum MOF: Simultaneous CO2 capture and catalysis

Abstract

Carbon dioxide (CO2) capture has become a hot topic in recent years because of global warming issues. However, most research has focused primarily on gas capture, with limited methods available for achieving both CO2 capture and conversion within a single material. Here, we synthesized FMU-101, a metal-organic framework (MOF) with metal-open sites, through the self-assembly of [1,1′-Biphenyl]-3,3′,5-tricarboxylic acid and lanthanide ions in a solvothermal environment. FMU-101 features hexagonal one-dimensional pores with a diameter of 1.4 nm. The presence of free dimethylamine cations and metal open sites in the channel contributes to its remarkable capability for selectively enriching CO2 from CO2/CH4 mixtures in dynamic breakthrough experiments. Furthermore, the metal-open sites in FMU-101 play a crucial role in CO2 fixation, serving as effective catalytic sites for converting the adsorbed CO2 into high-value chloropropylene carbonate, a versatile chemical intermediate. The segregation and conversion mechanisms were further elucidated through density-functional theory (DFT) calculations and Grand Canonical Monte Carlo (GCMC) simulations, which highlighted the critical role of metal-open sites in CO2 adsorption and transformation.

Keywords

• Lanthanum metal-organic frameworks
• Gas adsorption
• Catalytic conversion