A team of researchers from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) have developed a novel supercapacitor (SC)-assisted electrophotocatalysis which provides efficient defluorination of PTFE and PFAS at low temperatures.
The technique, published in the journal Angewandte Chemie International Edition, utilizes supercapacitors which allow for the generation of catalytically active species which can replace reducing agents commonly found in photocatalytic reactions.
This system provides effective electron injection into the carbon-fluorine bond of PTFE, establishing effective defluorination under mild conditions. Additionally, the method avoids the excessive use of co-reductants, while expanding from milligram level reactions to gram level. The team also notes promising applicability for the defluorination of PFAS molecules.
Thanks to the fast charging speeds, high efficiency, and long cycle life, supercapacitors can be used outdoors with sunlight as the energy source to effectively defluorinated PTFE. To confirm their results, the team utilized Raman spectroscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy to characterize the solid products.
The technique developed could provide new pathways towards environmental remediation of compounds such as PTFE and small molecule PFAS compounds.