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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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High-yield atmospheric water capture via bioinspired material segregation
Transforming atmospheric water vapor into liquid form can be a way to supply water to arid regions for uses such as drinking water, thermal management, and hydrogen generation. Many current methods rely on solid sorbents that cycle between capture and release at slow rates. We envision a radically different approach where water is transformed and directly captured into a liquid salt solution that is suitable for subsequent distillation or other processing using existing methods. In contrast to other methods utilizing hydrogels as sorbents, we do not store water within hydrogels—we use them as a transport medium. Inspired by nature, we capture atmospheric water through a hydrogel membrane “skin” at an extraordinarily high rate of 5.50 kg m^-2 d^-1 at a low humidity of 35%. and up to 16.9 kg m^-2 d^-1at higher humidities. For a drinking-water application, calculated performance of a hypothetical one-square-meter device shows that water could be supplied to two to three people in arid environments. This work is a significant step toward providing new resources and possibilities to water-scarce regions.
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- Award ID(s):
- 2239416
- PAR ID:
- 10574336
- Editor(s):
- Balazs, Anna
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 121
- Issue:
- 44
- ISSN:
- 0027-8424
- Subject(s) / Keyword(s):
- atmospheric water harvesting hydrogels convection mass transfer
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1073/pnas.2321429121
