Electrochemical Proof of Fluorophilic Interaction among Fluoro‐Carbon Chains

Abstract

We form self‐assembled monolayer (SAM) of fluoro‐carbon chain (C−F_SAM) or hydro‐carbon chain (C−H_SAM) to compare their interaction with surfactants containing C−F chains (PFOA, PFOS) or C−H chains (linear alkylbenzene sulphonate, LAS). We observe that the interaction between the C−F_SAM and the C−F chain is much stronger than that between the C−H_SAM and the C−H/C−F chain, and also stronger than that between the C−F_SAM and the C−H chain. The reason is due to the unique fluorophilic interaction among the C−F chains, which is similar with and thus confirm the mechanism for F‐extraction. This unique interaction among the C−F chains might shine new light on the development of fluorosurfactant's sensor and remediation.

Designing zeolites for the removal of aqueous PFAS: a perspective

“…The addition of fluorine on an alkyl chain has the dual effect of making the surface more hydrophobic, as well as providing a potential for fluorophilic interaction. 36 This type of adsorption could be extended to zeolite structures, with the internal siloxane surface providing additional hydrophobic surface for adsorption of fluoroalkyl chains, while cations and or T-atoms provide electrostatic charge for the head groups of PFAS molecules. Adjacent to silane grafting, surfactant modified zeolites have already shown the ability to adsorb negatively charged organic anionic pollutants.…”

A Critical Review on PFAS Removal from Water: Removal Mechanism and Future Challenges

“…The wide contact angle of n-hexadecane on PMO-NHCF-3 (128 • ) further demonstrated the material's significant oleophobicity, which is a unique feature of the fluoroalkyl group. As PFBA has a distinctive fluorous chemistry and a stiff structural C-F skeleton, fluorophilic interactions could further improve the attraction among PFBA and the bifunctional PMOs [159][160][161].…”

Coulometric Determination of Perfluoroalkyl Substances (PFAS) with the Thin-layer Electrolysis Flow Cell for the Ion Transfer

“…16 PFAS is redox-inactive species and has been detected by the following two strategies: (1) the indirect evaluation of the effect of PFAS on the electrochemical reaction of redox probes, (2) the direct detection of the transfer of PFAS ion at the interface between an aqueous sample solution and a membrane. The examples of (1) measure the effect of PFAS on the redox current or the impedance of the redox probes at the electrodes modified by PFAS, 17 molecular imprinting polymer selective for PFAS, [18][19][20][21][22] fluoroalkyl thiol, [23][24][25] perfluorinated anion exchange ionomer, 26 or metal-organic framework (MOF). 27 The improvement in selectivity for PFAS has been attempted based on the strong binding of PFAS to fluoroalkyl substances.…”

“…27 The improvement in selectivity for PFAS has been attempted based on the strong binding of PFAS to fluoroalkyl substances. 18,24,25,27,28 The redox probes are not only general redox species but also gas bubble 26,[29][30][31] or Ag nano particle. 28 The examples of (2) measure the current response 32,33 or the interfacial potential response 34 caused by the transfer of PFAS ion at the interface between an aqueous sample solution and an organic membrane.…”