Japanese scientists have found a new way that will help combat the increasing concentration of carbon dioxide in the earth’s atmosphere. The key to this method is a special porous coordination polymer (PCP) filled with zinc ions, which effectively absorbs CO2 from the atmosphere and, without spending a lot of energy, transforms it into useful organic compounds. Moreover, elements from such material can be included in everyday clothes, in packaging materials, etc., turning it all into a means of combating climate change.
The presence of zinc ions in the PCP polymer allows this material to absorb atmospheric carbon dioxide 10 times more efficiently than other similar materials can. Moreover, the PCP polymer lends itself to a regeneration procedure; its experimental samples withstood about 10 recovery cycles without loss of efficiency.
Note that the task of absorbing carbon dioxide from the atmosphere is quite difficult due to the low chemical activity of this compound. In this case, the solution to this problem was PCP polymers, also known as metal-organic structured materials (metal-organic framework, MOF). And the type of material used to absorb carbon dioxide has an organic component that resembles in structure a propeller with three blades.
X-ray structural analysis showed that when CO2 molecules approach the organic parts of the PCP polymer, the “propeller” rotates and the entire structure is rearranged, creating a reliable trap for the molecule. Moreover, the polymer structure is chosen such that it is initially “tuned” to carbon dioxide molecules, it practically does not react and does not capture molecules of other compounds and gases. And after the PCP polymer is completely filled with CO2 molecules, it is easily processed into polyurethane, which is widely used in the manufacture of clothing, packaging, household items, etc.
Note that the PCP polymer is far from the only option for converting atmospheric carbon dioxide to something else. Earlier this year, researchers from RMIT University, Australia, developed a method for directly converting CO2 to coal using a chemical reaction involving cerium metal. Researchers at Rice University, USA, have developed a device that turns CO2 into formic acid, from which it is then possible to produce liquid biofuels. And a key component of this device was a bismuth metal catalyst.
In the PCP polymer, unlike the above examples, zinc is used, a cheaper and more common metal. “This is one of the cheapest and greenest ways to capture carbon dioxide today,” said Susumu Kitagawa, a chemist at Kyoto University, “and, in addition, it allows you to convert gas to cyclic carbonates, which are raw materials.” for the pharmaceutical and petrochemical industries”.