Perfluoroalkyl acid precursor or weakly fluorinated organic compound? A proof of concept for oxidative fractionation of PFAS and organofluorines.

Organofluorine mass balance approaches are increasingly applied to investigate the occurrence of per- and polyfluoroalkyl substances (PFAS) and other organofluorines in environmental samples more comprehensively. Usually, complex samples prevent the identification and quantification of every fluorine-containing molecule. Consequently, large unidentified fractions between fluorine sum parameters such as extractable organic fluorine (EOF) and the sum of quantified analytes are frequently reported.

An optimized method for PFAS analysis using HR-CS-GFMAS via GaF detection.

The analysis of per- and polyfluoroalkyl substances (PFAS) via sum parameters like extractable organic fluorine (EOF) in combination with high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) is highly promising regarding fluorine sensitivity and selectivity. However, the HR-CS-GFMAS method includes several drying and heating steps which can lead to losses of volatile PFAS before the molecular formation step using e.g.

Non-extractable PFAS in functional textiles - characterization by complementary methods: oxidation, hydrolysis, and fluorine sum parameters.

Per- and polyfluoroalkyl substances (PFAS) are widely used for durable water-repellent finishing of different fabrics and textiles such as outdoor clothing, carpets, medical textiles and more. Existing PFAS extraction techniques followed by target analysis are often insufficient for detecting widely used side-chain fluorinated polymers (SFPs) that are barely or non-extractable. SFPs are typically copolymers consisting of a non-fluorinated backbone with perfluoroalkyl side-chains to obtain desired properties.

Quantification and characterization of PFASs in suspended particulate matter (SPM) of German rivers using EOF, dTOPA, (non-)target HRMS.

In this study, we compare analytical methods for PFAS determination-target analysis, non-target screening (NTS), direct total oxidizable precursor assay (dTOPA) and extractable organically bound fluorine (EOF). Therefore, suspended particulate matter (SPM) samples from German rivers at different locations in time series from 2005 to 2020 were analyzed to investigate temporal and spatially resolved trends. In this study 3 PFAS mass balances approaches were utilized: (i) PFAA target vs.

EOF and target PFAS analysis in surface waters affected by sewage treatment effluents in Berlin, Germany.

Per- and polyfluoroalkyl substances (PFAS) are emerging organic pollutants and can occur in surface and groundwater. To identify the degree of pollution in surface water with PFAS, often targeted HPLC-ESI-MS/MS has been employed in which commonly 30-40 compounds are analyzed. However, other PFAS and organofluorines remain undetected.

A fast and simple PFAS extraction method utilizing HR-CS-GFMAS for soil samples.

Here, we describe an optimized fast and simple extraction method for the determination of per- and polyfluorinated alkyl substances (PFASs) in soils utilizing high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS). To omit the bias of the solid phase extraction (SPE) step commonly used during the analysis of extractable organically bound fluorine (EOF) we optimized a fast and simple SPE-free extraction method. The developed extraction method consists of a liquid-solid extraction using acidified methanol without any additional SPE.

A Generalized Method for High-Speed Fluorination of Metal Oxides by Spark Plasma Sintering Yields Ta O F and TaO F with High Photocatalytic Activity for Oxygen Evolution from Water.

A general method to carry out the fluorination of metal oxides with poly(tetrafluoroethylene) (PTFE, Teflon) waste by spark plasma sintering (SPS) on a minute scale with Teflon is reported. The potential of this new approach is highlighted by the following results. i) The tantalum oxyfluorides Ta O F and TaO F are obtained from plastic scrap without using toxic or caustic chemicals for fluorination.

Determination of organically bound fluorine sum parameters in river water samples-comparison of combustion ion chromatography (CIC) and high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS).

In this study, we compare combustion ion chromatography (CIC) and high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) with respect to their applicability for determining organically bound fluorine sum parameters. Extractable (EOF) and adsorbable (AOF) organically bound fluorine as well as total fluorine (TF) were measured in samples from river Spree in Berlin, Germany, to reveal the advantages and disadvantages of the two techniques used as well as the two established fluorine sum parameters AOF and EOF. TF concentrations determined via HR-CS-GFMAS and CIC were comparable between 148 and 270 μg/L.

Interphase Formation of PEO:LiTFSI-LiPSCl Composite Electrolytes with Lithium Metal.

Composite polymer electrolytes (CPEs), consisting of solid electrolyte particles embedded within a solid polymer electrolyte matrix, are promising materials for all-solid-state batteries because of their mechanical properties and scalable production processes. In this study, CPEs consisting of PEO:LiTFSI blended with 1, 10, and 40 wt % (CPE40) of the LiPSCl electrolyte filler are prepared by a slurry-based process. The incorporation of LiPSCl improves the lithium-ion conductivity from 0.

Properties of the Interphase Formed between Argyrodite-Type LiPSCl and Polymer-Based PEO:LiTFSI.

All-solid-state lithium metal batteries using thiophosphate solid electrolytes (SE) present a promising alternative to state-of-the-art lithium-ion batteries due to their potentially superior energy and power. However, reactions occurring at the lithium metal | SE interface result in an increasing internal resistance and limited cycle life. A stable solid polymer electrolyte (SPE) may be used as protective interlayer to prevent the SE from direct contact and reaction with lithium metal.

Structure Evolution and Reactivity of the ScV O (0 ≤ x ≤ 2.0) System.

Solid oxide fuel cells (SOFCs) are solid-state electrochemical devices that directly convert chemical energy of fuels into electricity with high efficiency. Because of their fuel flexibility, low emissions, high conversion efficiency, no moving parts, and quiet operation, they are considered as a promising energy conversion technology for low carbon future needs. Solid-state oxide and proton conducting electrolytes play a crucial role in improving the performance and market acceptability of SOFCs.