Carbon nanotubes are supermaterials that can be stronger than steel and more conductive than copper. The reason they're not in every application from batteries to tires is that these properties only show up in the tiniest nanotubes, which are extremely expensive. A new process was developed that can make these materials from carbon dioxide drawn from the air, in a way that is much less expensive than other methods. These materials could impact how emissions can be used in future technology.
The process uses electrochemistry to pull apart carbon dioxide into elemental constituents of carbon and oxygen, and stitch together, with nanometer precision, those carbon atoms into new forms of matter. Tiny nanoparticles 10,000 times smaller than a human hair can be produced from coatings on stainless steel surfaces. A process called Ostwald ripening — where the nanoparticles that grow the carbon nanotubes change in size to larger diameters — is a key contender against producing the infinitely more useful size. This was partially overcome by tuning electrochemical parameters to minimize these large nanoparticles.