UC Riverside

The introduction of C3-symmetric pore-partitioning agents, in the form of either molecular ligand such as 2,4,6-tri(4-pyridinyl)-1,3,5-triazine (tpt) or metal-complex clusters, into hexagonal channels of MIL-88/MOF-235 type (the acs net) to create pacs-type (partitioned acs) crystalline porous materials is an effective strategy to develop high-performance gas adsorbents. In the first part, inspired by the synthetic chemistry of COF-1, we developed integrated COF-MOF chemistry through co-assembly of [B3O3(py)3] COF-type trimers and [(M3(OH)(COO)6] MOF-type trimers as a new method for pore-space partition. With this strategy, the coordination-driven assembly of the acs framework occurs concurrently with the COF-1-type condensation of pyridine-4-boronic acid into a C3-symmetric trimeric boroxine molecule leading to a new family of pacs materials. The new boroxine-based pacs materials exhibit dramatically enhanced NH3 sorption properties. In the second part, we further explored and utilized the method in the first part to let the self-assembly of the acs framework react simultaneously with the trimerization of three different monomers. Three monomers including 4-cyanopyridine, 4-vinylpyridine, and pyridine-4-boronic acid trimerized into 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine (TPT), 1,3,5-tri(pyridin-4-yl)-cyclohexane (TPC), and 2,4,6-tri(4-pyridinyl)-1,3,5-boroxine (TPB) during the pacs materials formation. New materials exhibit excellent C2H2/CO2 gas separation performance. In the third part, we lengthened the monomer from pyridine-4-boronic acid to 4-(pyridin-4-yl) phenyl boronic acid and prepared two new pacs compounds with similar surface areas. C3H8 and C3H6 isothermal adsorption studies on these two compounds revealed the host-guest interaction sites in structures. In summary, the pore-space partition of crystalline porous materials by monomer trimerization in this dissertation is a novel and efficient method for gas captures and host-guest interaction studies.