Abstract
Sorbents for direct air capture (DAC) of CO2 typically employ a chemisorbing material that requires regeneration at elevated temperatures, which is an energy-intensive step. Here, we developed composites of metal organic framework (MOF) with a functional ionic liquid (IL) at 5, 20, and 35 wt % loading, capable of CO2 chemisorption and regeneration by moisture-swing coupled microwave (MW) irradiation. In dynamic breakthrough measurements, CO2 from synthetic air (500 ppm of CO2) was selectively absorbed (0.5 mmol/g at 30 °C) and then rapidly released (2-4 min) by dielectric heating at 60 °C. The developed IL/MOF composites demonstrate (1) targeted energy transfer to the IL domains where CO2 is released due to dielectric heating upon MW irradiation and (2) a fast desorption rate due to large surface area offered by the MOF architecture. This study establishes carbon capture through surface enhancement of a porous substrate with ILs for future DAC processes that can be powered by sustainable energy sources.
| Original language | English |
|---|---|
| Pages (from-to) | 3854-3861 |
| Number of pages | 8 |
| Journal | ACS Materials Letters |
| Volume | 6 |
| Issue number | 8 |
| DOIs | |
| State | Published - Aug 5 2024 |
Funding
This study was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Chemical Sciences, Geosciences, & Biosciences (CSGB) Division, under Award No. DE-SC0022214. The authors acknowledge the Soft Matter Characterization Laboratory for the access to TGA at Case Western Reserve University (CWRU). STEM and EELs images were collected at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. The authors thank Cameron Taylor and Emily Pentzer (Texas A&M University) for XRD and SEM-EDS measurements. Credit for table of content graphics: Adam Malin at ORNL. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05\u201300OR22725 with the U.S. Department of Energy (DOE). The U.S. government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. government purposes. The DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ).
