New crystal captures carbon from the air, even in the presence of water

One way to mitigate climate change could be to capture carbon dioxide (CO₂) from the air. So far this has been difficult, since the presence of water prevents the adsorption of CO₂. Complete dehydration is a costly process. Scientists have now created a stable and recyclable material, where the micropores within the crystal have different adsorption sites for carbon dioxide and water.

"As far as I know this is the first material that captures CO₂ in an efficient way in the presence of humidity. In other cases there is competition between water and carbon dioxide and water usually wins. This material adsorbs both, but the CO₂ uptake is enormous," says Osamu Terasaki, Professor at the Department of Materials and Environmental Chemistry at Stockholm University.

The new material is called SGU-29, named after Sogang University in Korea, and is the result of international cooperation. It is a copper silicate crystal. The material could be used for capturing carbon dioxide from the atmosphere, and especially to clean emissions.

"CO₂ is always produced with moisture, and now we can capture CO₂ from humid gases. Combined with other systems that are being developed, the waste carbon can be used for new valuable compounds. People are working very hard and I think we will be able to do this within five years. The most difficult part is to capture carbon dioxide, and we have a solution for that now," says Osamu Terasaki.