Inorganic Anion-based Functional Porous Materials for Selective Gas Separations

This dissertation aims to develop advanced inorganic anion based porous adsorbents featuring confined pore space for adsorptive separations The structural tunability and high versatility of metal organic frameworks, or porous coordination polymers, endow them with the capability of facilitating molecular separation through rational design and engineering the intrinsic confined nanospace. We leveraged the structural uniqueness of cyanide based anion nitroprusside and new fluorinated anion [WO2F4]2- and successfully implemented them into porous crystalline frameworks. By experimental gas sorption, in situ characterizations and computational molecular simulations, we unraveled the role of anion ligand, framework dynamics and host guest interactions in the specific gas separations. In this dissertation, we studied the ultramicroporous inorganic anion based materials for selective CO2 capture and propylene /propane separations : 1) Electrostatically driven selective adsorption of carbon dioxide from acetylene in a n ultramicroporous Cd-NP . 2) Carbon capture from nitrogen and methane within the nanoconfinement of Cd-NP with open cadmium sites under dry and humid conditions. 3) An ultramicroporous cyanide based compound, Ni-NP, with open metal sites enables efficient separation of propylene from propane 4) A new fluorinated anion pillar based MOF, UTSA-400, is synthesized , structurally characterized, and systematically investigated for the realization of molecular sieving propylene from propane with optimal binding affinity.