Envisioning the “Air Economy” — Powered by Reticular Chemistry and Sunlight for Clean Air, Clean Energy, and Clean Water
- Currently 100,000 MOFs structures are known. The pore diameter range from 5 Å to 100 Å. Ultra-high surface area of up to 7,000 m2/g
- Captureing CO2 from air requires new materials capable of trapping carbon dioxide at 400-ppm levels.
- Zeolite (0.25 ~ 1.4 mmol/gCO2) requires very high regeneration T. Polymers (very low capacity), silica (0.1 ~ 1.8 mmol/gCO2), MOFs (0.1 to 4 mmol/gCO2) should be functionalized with primary amines to capture CO2. No MOF which can be recycled over a large number of cycles is yet to be reported.
- The current estimate of CO2 capture for direct air capture (DAC) systems spans a range of $100 ~ $1000/tCO2 while flue gas capture techniques can produce $70 ~ $100/tCO2
- Effective electro-catalysis coupled with high-efficiency stateof-the-art solar junctions can already deliver green hydrogen at ~30% solar-to-hydrogen efficiency.
- Water harvesting from air is already commercialized by Water Harvesting Inc. Their latest device employs only 200 g of MOF and can harvest water at the rate of 40 L per kilogram of MOF per day. The lifetime of MOF is 6 years. MOF can be treated with strong acid to dissociate the linker from the metal and resynthesized in water.
