2019 Engineering Sustainable Development

Cationic Network Polymers: The Impact of Counter-Anions and Porosities on for Atmospheric CO2 Fixation and Cyclic Carbonate Formation

Authors

Doyun Kim, KAIST
Non-redox carbon dioxide utilization through cycloaddition of CO2 to epoxides offer great promise, but suffer from suitable heterogeneous catalysts are vital for their widespread implementation. We recently reported a highly efficient heterogeneous catalyst for CO2 addition to epoxides based on a newly identified active catalytic pocket consisting of imidazolinium moieties, but there is a clear need for industrial implementation through systematic optimization. Different counter-anions and positively charged imidazolinium units in their backbones was prepared for optimizing in quantitative yield to cyclic carbonate. Catalytic actives sites derived from the counter-anions were characterized with heat of adsorption (Qst) to identify CO2 affinities and less-reactive substrates to compare catalytic activities. Also, silica template produced increased porosity in catalysts that enhanced diffusion in porous networks. The systematic optimization of counter-anions and porosity with catalytic activities provides attractive new paths for further scale-up and industrial implementation.