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Abstract Global reliance on fossil fuel combustion for energy production has contributed to the rising concentration of atmospheric CO2, creating significant global climate challenges. In this regard, direct air capture (DAC) of CO2from the atmosphere has emerged as one of the most promising strategies to counteract the harmful effects on the environment, and the further development and commercialization of this technology will play a pivotal role in achieving the goal of net‐zero emissions by 2050. Among various DAC adsorbents, metal–organic frameworks (MOFs) show great potential due to their high porosity and ability to reversibly adsorb CO2at low concentrations. However, the adsorption efficiency and cost‐effectiveness of these materials must be improved to be widely deployed as DAC sorbents. To that end, this perspective provides a critical discussion on several types of benchmark MOFs that have demonstrated high CO2capture capacities, including an assessment of their stability, CO2capture mechanism, capture‐release cycling behavior, and scale‐up synthesis. It then concludes by highlighting limitations that must be addressed for these MOFs to go from the research laboratory to implementation in DAC devices on a global scale so they can effectively mitigate climate change.
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This content will become publicly available on October 17, 2026
Distributed direct air capture by carbon nanofiber air filters
The rising atmospheric CO2concentration is one of the biggest challenges human civilization faces. Direct air capture (DAC) that removes CO2from the atmosphere provides great potential in carbon neutralization. However, the massive land use and capital investment of centralized DAC plants and the energy-intensive process of adsorbent regeneration limit its wide employment. We develop a distributed carbon nanofiber (CNF)–based DAC air filter capable of adsorbing CO2downstream in ventilation systems. The DAC air filter not only has the potential to remove 596 MtCO2year−1globally but can also decrease energy consumption in existing building systems. The CNF-based adsorbent has a capacity of 4 mmol/g and can be regenerated via solar thermal or electrothermal methods with low carbon footprints. Through life cycle assessment, the CNF air filter shows a carbon removal efficiency of 92.1% from cradle to grave. Additionally, techno-economic analysis estimates a cost of $209 to 668 in capturing and storing 1 tonne of CO2from direct air.
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- Award ID(s):
- 2114117
- PAR ID:
- 10649700
- Publisher / Repository:
- American Association for the Advancement of Science
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 11
- Issue:
- 42
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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