A new method of breaking down harmful chemicals with carbon-fluorine bonds

What do raincoats and non-stick cooking sprays have in common? The substances that give these materials their unique qualities are called “forever chemicals:” compounds that break down very slowly because of stable chemical bonds. Specifically, these strong bonds are between the atoms carbon and fluorine. Carbon-fluorine (C-F) bonds can stay around for more than a millennium, polluting nature and even causing human disease such as cancer and immunodeficiency. Finding energy efficient ways to break C-F bonds has been a challenge, but two groups have recently reported exciting advancements.

Two recent studies tackled this challenge by utilizing different catalysts, or proteins that help chemical reactions happen faster. Both catalysts transfer energy absorbed from visible light to target molecules in order to break C-F bonds, a process called “photocatalysis.” The catalysts have unique solutions to the problem; one directly changes the carbon-fluorine bond to a carbon-hydrogen bond and the other breaks down larger molecules into smaller parts which can be more easily recycled.  Both solutions elegantly tackle the fundamental problem of breaking C-F bonds.

Though these catalysts don’t yet work on the complex, synthetic materials with C-F bonds, such as Teflon, they are an important step in our ability to control the organic chemistry of strong C-F bonds. With more optimization and testing in natural settings, such as in bulk water with pollutants, these catalysts could offer a major improvement to human health and to reducing pollution in the environment. 

These studies were led by Xin Liu with corresponding authors Robert S. Paton, Niels H. Damrauer and Garret M. Miyake at Colorado State University and Hao Zhang with corresponding authors Jian-Ping Qu and Yan-Biao Kang at University of Science and Technology of China.

Managing Correspondent: Olivia Lavidor

Press Article: ‘Forever’ chemicals can be destroyed with clever chemistry — now test these techniques outside the lab (Nature Briefing)

Original Journal Articles: Photocatalytic low-temperature defluorination of PFASs (Nature) and Photocatalytic C–F bond activation in small molecules and polyfluoroalkyl substances (Nature)

Image Credit: Tara Winstead/pexels