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Abstract Carbon capture and sequestration (CCS) from industrial point sources and direct air capture are necessary to combat global climate change. A particular challenge faced by amine‐based sorbents—the current leading technology—is poor stability towards O2. Here, we demonstrate that CO2chemisorption in γ‐cylodextrin‐based metal–organic frameworks (CD‐MOFs) occurs via HCO3−formation at nucleophilic OH−sites within the framework pores, rather than via previously proposed pathways. The new framework KHCO3CD‐MOF possesses rapid and high‐capacity CO2uptake, good thermal, oxidative, and cycling stabilities, and selective CO2capture under mixed gas conditions. Because of its low cost and performance under realistic conditions, KHCO3CD‐MOF is a promising new platform for CCS. More broadly, our work demonstrates that the encapsulation of reactive OH−sites within a porous framework represents a potentially general strategy for the design of oxidation‐resistant adsorbents for CO2capture.
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Carbon Capture Beyond Amines: CO 2 Sorption at Nucleophilic Oxygen Sites in Materials
Abstract Carbon capture and utilization or sequestration and direct air capture will be needed to reduce atmospheric levels of greenhouse gases over the next century. Current amine‐based technologies bind CO2with high selectivities but suffer from poor oxidative and thermal stabilities. Herein, we discuss understudied sorbents based on oxygen nucleophiles, including metal oxides and hydroxides, hydroxide‐containing polymers, and hydroxide‐based metal–organic frameworks. In general, these materials display improved oxidative stabilities compared to traditional amine‐based sorbents. We outline the challenges and opportunities offered by these alternative sorbents for carbon capture applications.
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- Award ID(s):
- 2047627
- PAR ID:
- 10379725
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemNanoMat
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2199-692X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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