Authors:	Lange, Martin Alexander Khan, Ibrahim Opitz, Phil Hartmann, Jens Ashraf, Muhammad Qurashi, Ahsanulhaq Prädel, Leon Panthöfer, Martin Cossmer, Antje Pfeifer, Jens Simon, Fabian Au, Marcus von der Meermann, Björn Mondeshki, Mihail Tahir, Muhammad Nawaz Tremel, Wolfgang
Title:	A generalized method for high-speed fluorination of metal oxides by spark plasma sintering yields Ta3O7F and TaO2F with high photocatalytic activity for oxygen evolution from water
Online publication date:	26-Apr-2022
Year of first publication:	2021
Language:	english
Abstract:	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 Ta3O7F and TaO2F are obtained from plastic scrap without using toxic or caustic chemicals for fluorination. ii) Short reaction times (minutes rather than days) reduce the process time the energy costs by almost three orders of magnitude. iii) The oxyfluorides Ta3O7F and TaO2F are produced in gram amounts of nanoparticles. Their synthesis can be upscaled to the kg range with industrial sintering equipment. iv) SPS processing changes the catalytic properties: while conventionally prepared Ta3O7F and TaO2F show little catalytic activity, SPS-prepared Ta3O7F and TaO2F exhibit high activity for photocatalytic oxygen evolution, reaching photoconversion efficiencies up to 24.7% and applied bias to photoconversion values of 0.86%. This study shows that the materials properties are dictated by the processing which poses new challenges to understand and predict the underlying factors.
DDC:	540 Chemie 540 Chemistry and allied sciences
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 09 Chemie, Pharmazie u. Geowissensch.
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-6903
Version:	Published version
Publication type:	Zeitschriftenaufsatz
License:	CC BY-NC-ND
Information on rights of use:	https://creativecommons.org/licenses/by-nc-nd/4.0/
Journal:	Advanced materials 33 20
Pages or article number:	2007434
Publisher:	Wiley-VCH
Publisher place:	Weinheim
Issue date:	2021
Publisher DOI:	10.1002/adma.202007434
Appears in collections:	JGU-Publikationen