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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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Catalyst-TiO(OH)2 could drastically reduce the energy consumption of CO2 capture
Abstract Implementing Paris Climate Accord is inhibited by the high energy consumption of the state-of-the-art CO2capture technologies due to the notoriously slow kinetics in CO2desorption step of CO2capture. To address the challenge, here we report that nanostructured TiO(OH)2as a catalyst is capable of drastically increasing the rates of CO2desorption from spent monoethanolamine (MEA) by over 4500%. This discovery makes CO2capture successful at much lower temperatures, which not only dramatically reduces energy consumption but also amine losses and prevents emission of carcinogenic amine-decomposition byproducts. The catalytic effect of TiO(OH)2is observed with Raman characterization. The stabilities of the catalyst and MEA are confirmed with 50 cyclic CO2sorption and sorption. A possible mechanism is proposed for the TiO(OH)2-catalyzed CO2capture. TiO(OH)2could be a key to the future success of Paris Climat e Accord.
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- Award ID(s):
- 1632899
- PAR ID:
- 10154301
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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