Understanding the role of metal and oxygen in the redox process of layered 3d transition metal oxides is crucial to build high density and stable next generation Li-ion batteries. We combine hard X-ray photoelectron spectroscopy and ab-initio-based cluster model simulations to study the electronic structure of prototypical end-members LiCoO2 and CoO2. The role of cobalt and oxygen in the redox process is analyzed by optimizing the values of d-d electron repulsion and ligand-metal p-d charge transfer to the Co 2p spectra. We clarify the nature of oxidized cobalt ions by highlighting the transition from positive to negative ligand-to-metal charge transfer upon Li+ de-intercalation.
@article{arxiv.2306.03096,
title = {Self-regulated ligand-metal charge transfer upon lithium ion de-intercalation process from LiCoO2 to CoO2},
author = {Roberto Fantin and Ambroise van Roekeghem and Anass Benayad},
journal= {arXiv preprint arXiv:2306.03096},
year = {2023}
}
Comments
Using X-ray photoelectron spectroscopy and ab-initio simulations, this study reveals the changes in electronic structure upon discharge for LixCoO2, an archetypal cathode material for lithium-ion batteries