Afficher la notice abrégée

Exploring the short and long-range order in connection with fluorine content in mixed anions copper hydroxyfluorides

hal.structure.identifierInstitut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
dc.contributor.authorHYRONDELLE, Helies
hal.structure.identifierInstitut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
dc.contributor.authorSUCHOMEL, Matthew
hal.structure.identifierInstitut des Sciences Moléculaires [ISM]
dc.contributor.authorRODRIGUEZ, Vincent
hal.structure.identifierInstitut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
dc.contributor.authorFARGUES, Alexandre
hal.structure.identifierInstitut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
dc.contributor.authorDURAND, Étienne
hal.structure.identifierInstitut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
dc.contributor.authorWEILL, François
hal.structure.identifierInstitut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
dc.contributor.authorDEMOURGUES, Alain
dc.date.issued2024
dc.identifier.issn1293-2558
dc.description.abstractEnHydroxyl-rich (Cu-LF) and Fluorine-rich (Cu–HF) copper hydroxyfluorides Cu(OH)2-xFx (x = 0.4–0.5 and x = 0.9–1.5) were prepared by precipitation route followed by hydrothermal process where the starting pH and the HF molar content play a key role. Based on powder XRD and PDF analysis, long range and short order were evidenced with various Cu–O/F bondlengths illustrating the Jahn-teller distortion as well as the Cu–Cu intra-sheet and interslab interactions. Tuning the fluorine content allows chemical bonding modulation by antagonist effect, resulting for instance in the weakening of H bonding in the hydroxyl-rich compound. When the fluorine content increases, the average structures evolve from a disordered network with a random distribution of anions in the vicinity of Cu2+ in Cu-LF to a well ordered mixed anions phase where Cu(OH)3F3/Cu(OH)2F4/Cu(OH)5F distorted octahedra are close to C2h point group symmetry. Raman spectroscopy confirm the average structural features with the point group symmetry. One should outline in Cu–HF composition, stronger CuF3(OH)3 octahedron stiffness associated to a stretching O–H mode at lower frequency, synonymous of O–H bond weakening and consequently stronger hydrogen bonding in agreement with PDF analysis. UV–visible–NIR spectra show in Cu–HF hydroxyfluoride, an increase of the optical band gap of 0.6 eV and a decrease of Cu2+(3 d9) crystal field splitting of 0.1 eV in agreement with the larger fluorine content. However, the dxz-dyz orbital splitting increases of 0.2 eV in Cu–HF in good agreement with the C2h point group symmetry and the related distortion. Finally, whereas the hydroxyl-rich Cu-LF phase decomposes into CuO at T > 300 °C, the Fluorine rich Cu–HF compound lead at T > 320 °C to the formation of CuF2, Cu2O in addition to CuO. This unusual reduction process Cu2+ → Cu+ at low temperature is associated to the strengthening of Cu–O/F and Cu–Cu bonding in the basal plane of Cu(OH)3F3 distorted octahedron.
dc.description.sponsorshipNanomatériaux oxy-hydroxyflurorures inorganiques, une nouvelle famille de catalyseurs basiques sélectifs et modulables - ANR-21-CE08-0020
dc.language.isoen
dc.publisherElsevier
dc.title.enExploring the short and long-range order in connection with fluorine content in mixed anions copper hydroxyfluorides
dc.typeArticle de revue
dc.identifier.doi10.1016/j.solidstatesciences.2023.107384
dc.subject.halChimie/Matériaux
bordeaux.journalSolid State Sciences
bordeaux.page107384
bordeaux.volume147
bordeaux.peerReviewedoui
hal.identifierhal-04331803
hal.version1
hal.popularnon
hal.audienceInternationale
hal.origin.linkhttps://hal.archives-ouvertes.fr//hal-04331803v1
bordeaux.COinSctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Solid%20State%20Sciences&rft.date=2024&rft.volume=147&rft.spage=107384&rft.epage=107384&rft.eissn=1293-2558&rft.issn=1293-2558&rft.au=HYRONDELLE,%20Helies&SUCHOMEL,%20Matthew&RODRIGUEZ,%20Vincent&FARGUES,%20Alexandre&DURAND,%20%C3%89tienne&rft.genre=article


Fichier(s) constituant ce document

FichiersTailleFormatVue

Il n'y a pas de fichiers associés à ce document.

Ce document figure dans la(les) collection(s) suivante(s)

Afficher la notice abrégée