S=1/2 chain in BiVO3F: spin-dimers versus photoanodic properties - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Journal of the American Chemical Society Année : 2021

S=1/2 chain in BiVO3F: spin-dimers versus photoanodic properties

Résumé

BiVO3F was prepared, characterized and identified as the unique example of bismuth vanadyl oxyhalide with paramagnetic V 4+ centres. Its crystal structure shows 1D magnetic units with rare alternation of edge sharing O-O and F-F µ2 bridges along the octahedral chains. Structural pairing across the O2 edges induces antiferromagnetic spin dimers(S=0) with J/Kb300K, ⁓15 times greater than the exchange across the F2 bridges, within a non-ordered magnetic ground state. Despite multiple compositional, structural, and electronic analogies with the BiVO4 scheelite compound, one of the most promising photo-anode for solar water splitting, the photo activity of BiVO3F is relatively modest, partially due to this electronic pairing playing for fast electron-hole recombination. Similar to monoclinic-VO2, the V 4+ spin dimerization plays against the singlet → triplet electronic photo-excitation, but brings potential carrier lifetime benefits. The reduction of the bandgap from Eg 2.4 eV to 1.7 eV after incorporation of d 1 cations in BiVO4 makes BiVO3F an inspiring compound for local modifications toward an enhanced photo-active material. The direct d → d transition provides a significant enhancement of the visible light capture section, and opens a prospective route for the chemical design of performant photoanodes with a mixed anionic sublattice.

Domaines

Chimie
Fichier principal
Vignette du fichier
HALL-BIVO3F.pdf (1.53 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-03290791 , version 1 (19-07-2021)

Identifiants

Citer

Olivier Mentré, Miguel A Juárez-Rosete, Sebastien Saitzek, Cintli Aguilar-Maldonado, Marie Colmont, et al.. S=1/2 chain in BiVO3F: spin-dimers versus photoanodic properties. Journal of the American Chemical Society, 2021, 143 (18), pp.6942-6951. ⟨10.1021/jacs.1c00621⟩. ⟨hal-03290791⟩
31 Consultations
105 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More