Molecular engineering in a family of pillared-layered metal-organic frameworks for tuning gas adsorption behavior

In this work, inspired by a water-assisted three-dimensional supramolecular structure 1 , we use a mixed-ligand strategy to form a 3D pillared-layered matrix by the introduction of linear ligands to compete against the water molecules. The resulting analogue microporous MOFs of 2-H , 2-F and 2-N , decorated with different functional groups, similarly show the CO 2 uptake. Thanks to the negligible N 2 adsorption capacity, enhanced selective adsorption towards CO 2 is achieved in compound 2-N . That is, we present here an alternative plan for the high CO 2 selective adsorption performance. In addition, the structure stability and moderate affinity for CO 2 of these microporous MOFs endow them with excellent reusability. Three Co-based MOFs were obtained via a mixed-ligand strategy. One of them performs an extra high CO 2 /N 2 selectivity because of a negligible N 2 adsorption, which originate from a weak interaction between its framework and nitrogen molecules.