Functional Materials for Carbon Dioxide Capture and Conversion
Capture. We fabricated poly(ionicliquid)-ionic liquid composites and encapsulated ionic liquids with graphene oxide-polyurea shell specifically for CO2 filtration from air in confined spaces. The challenge we are addressing in this field is the low gravimetric CO2 capacity of existing separation materials, inadequate surface area for gas-liquid contact and leaching of liquid from its support upon variable pressures. We synthesize and formulate ionic liquid mixtures to increase gravimetric CO2 uptake and in-situ cast it from its solution with poly(ionic liquid). This strategy itself is not sufficient for the membrane technology to function effectively in microgravity. Therefore, we further reinforce these membranes with graphene oxide sheets and capsules of ionic liquids.
For IL capsules, we partner with Prof. Emily Pentzer at the Department of Materials Science and Engineering at Texas A&M University.
Conversion. CO2 is a waste product of fossil-fuel combustion. It is considered a green house gas. Therefore, conversion of CO2 at its source to value added products is appealing for various reasons: (1) cheap carbon source possibly for synthetic hydrocarbons, (2) environmentally friendly, and (3) introduces more incentive to reduce emissions. Electrochemical reduction of CO2 requires a suitable catalyst to reduce overpotentials and improve selectivity; yet it is less demanding in terms of temperature and pressure, compared to other conversion processes involving chemical reductions.
Electro-reduction of Carbon Dioxide
Since ionic liquids are essentially electrolytes and have high CO2 solubilities, we work towards answering the question: How do ionic liquids modulate the energy landscape and conversionproducts of the electrochemical CO2 reduction?
This project aims to expand the design space of electrocatalysts and improve efficiency for CO2 reduction by combining heterogeneous and homogenous catalysis mediated by ionic liquids.