Selective CO₂ Capture in Metal–Organic Frameworks with Azine-Functionalized Pores Generated by Mechanosynthesis

Two new three-dimensional porous Zn(II)-based metal–organic frameworks, containing azine-functionalized pores, have been readily and quickly isolated via mechanosynthesis, by using a nonlinear dicarboxylate and linear N-donor ligands. The use of nonfunctionalized and methyl-functionalized N-donor ligands has led to the formation of frameworks with different topologies and metal–ligand connectivities and therefore different pore sizes and accessible volumes. Despite this, both metal–organic frameworks (MOFs) possess comparable BET surface areas and CO 2 uptakes at 273 and 298 K at 1 bar. The network with narrow and interconnected pores in three dimensions shows greater affinity for CO 2 compared to the network with one-dimensional and relatively large pores—attributable to the more effective interactions with the azine groups.