(611e) Surface Functionalized Liquid-Like Nanoparticle Ionic Materials for CO2 Capture

Park, Y., Columbia University
Lin, K. A., Columbia University
Park, A. H. A., Columbia University

Because ionic liquids have a unique ?self-designable? characteristic, the physical and chemical structure of ionic liquids can be modified for various research and industrial applications such as synthesis, biocatalysis, electrochemistry, and separation. Moreover, most of ionic liquids exhibit environmentally benign physicochemical properties such as negligible vapor pressure with excellent thermal stability and solvating property, which can significantly reduce the emission of solvent during the industrial processes. Recently, ionic liquids have been applied to CO2 capture and storage (CCS) technology. Particularly, task-specific ionic liquids which contain alkaline groups such as amines have been developed as an alternative option to the conventional amine-based solvents (e.g., MEA solvent). In this study, liquid-like ionic materials called nanoparticle ionic materials (NIMs) are designed and synthesized. NIMs are molecular analog of ionic liquid, which consist of inorganic nanoparticle and amine-functionalized corona. By tethering corona chains to nanoparticle cores, additional free volume is created with an engineered canopy structure. It has been suggested both theoretically and experimentally that greater the frustration between corona chains would lead to improved CO2 capture by NIMs. This entropy effect allows greater CO2 capture by NIMs compared to conventional ionic liquids. A series of analytical techniques including TEM, TGA, ATR FT-IR and NMR spectroscopy are employed to investigate the physical and chemical structures of NIMs during their synthesis and CO2 capture. Next, as the amine functional groups are added along the length of the corona chain, the CO2 capture capacity of NIMs is further improved. The effects of temperature, CO2 partial pressure and humidity on the CO2 capture capacity, selectivity and recyclability of task-specific NIMs are investigated. The findings from this study will provide valuable knowledgebase for novel organic-inorganic hybrid materials that can be applied to various environmental and energy systems including CCS with the optimized enthaphic and entropic controls.