Researchers at the University of Texas Dallas have developed a new way of capturing potentially harmful gasses in a metal-organic framework, or MOFs. MOFs are composed of metal-ions and organic linker molecules.
In the pores or cells of these honeycomb-like structures, molecules can be trapped thanks to adsorption, but some some molecules are too weakly adsorbed to remain within the framework. This is where the UT researchers' work comes in. Much like the wax that seals the cells of a bee's honeycomb, a monolayer created from vapors of ethylenediamine, or EDA, were used to seal the MOFs. In doing so, the researchers have made it possible to trap gasses such as carbon dioxide, sulfur dioxide, and nitric oxide. The monolayer trapping in gas measures less than 1 nanometer in thickness.
To quantify how much gas was trapped and remained in the EDA-capped MOF structures, researchers used time-resolved, in-situ infrared spectroscopy, testing the efficiency of this molecular “cork” to trap weakly adsorbed gases.
Testing revealed that the EDA vapor was able to effectively retain the greenhouse gas carbon dioxide for up to a day.
Dr. Kui Tan, lead author of the published work, speculates that potential applications might include storage and release of hydrogen or natural gas to fuel a car, or could be used industrially for trapping and separating dangerous gases to prevent entry into the atmosphere.
To learn more about this research, see the open-access article in Nature.