Article Dans Une Revue Nature Materials Année : 2025

Clarifying the origin of molecular O2 in cathode oxides

Biao Li

Résumé

Anionic redox has reshaped the conventional way of exploring advanced cathode materials for Li-ion batteries. However, how anions participate in the redox process has been the subject of intensive debate, evolving from electron holes to O-O dimerization and currently to a focus on trapped molecular O2 based on high-resolution resonant X-ray inelastic scattering research. Here we show that the resonant X-ray inelastic scattering signal of molecular O2 is not exclusive to Li-rich oxide cathodes, but appears consistently in O-redox-inactive oxide materials even with a short beam exposure time as low as 1 min, indicating that molecular O2 species are not directly related to voltage hysteresis and voltage decay. We further demonstrated that molecular O2 is not a direct product of electrochemistry but more likely a consequence of the core excitation process in resonant X-ray inelastic scattering, for which the possible scenarios of the dissociation of 'M-(O-O)'-like species on beam excitation must be considered. Collectively, our results reconcile the conflicting reported results on the (non-)observation of molecular O2 signal collected from different beamlines and suggest that molecular O2 is not the energetic engine of new battery oxide cathodes.

Domaines

Fichier principal
Vignette du fichier
ACCEPTED_OriginO2.pdf (3.53 Mo) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)
Licence

Dates et versions

hal-04994524 , version 1 (04-02-2026)

Licence

Identifiants

Citer

Xu Gao, Biao Li, Kurt Kummer, Andrey Geondzhian, Dmitry Aksyonov, et al.. Clarifying the origin of molecular O2 in cathode oxides. Nature Materials, 2025, 24, pp.743-752. ⟨10.1038/s41563-025-02144-7⟩. ⟨hal-04994524⟩
290 Consultations
136 Téléchargements

Altmetric

Partager

  • More