23 Oct 2024

COF-999 captures carbon dioxide from open air over more than 100 cycles

Advanced materials and metamaterialsClimate and environment
AI illustration · Illustrative scene, not a photograph of the specific device or experiment.

What was demonstrated

An olefin-linked covalent organic framework with polyamines grown in its pores (COF-999) took up 0.96 mmol of CO2 per gram under dry conditions and 2.05 mmol per gram at 50% relative humidity, both from 400 ppm CO2. It reached half capacity in 18.8 minutes, regenerated at 60 degrees C, and retained full performance over more than 100 adsorption-desorption cycles in the open air of Berkeley, California.

Why it matters

Low regeneration temperature and stability in real outdoor air address two of the main cost drivers for direct air capture sorbents.

Caveats

  • Results are at gram scale in a laboratory set-up; no pilot-scale contactor was tested.
  • 100 cycles is far fewer than the many thousands a commercial sorbent would face.
  • Synthesis cost and scalability of the framework were not established.

Technology profiles

Sources

  1. peer reviewed paper
    Carbon dioxide capture from open air using covalent organic frameworks
    Zihui Zhou, Tianqiong Ma, Heyang Zhang et al.. Nature, 23 Oct 2024. DOI: 10.1038/s41586-024-08080-x.

Last reviewed 20 Oct 2026.