The Wadsley-Roth niobates for stable, fast lithium-ion diffusion battery anodes: first principles modelling combined with experiment
Crystallographic-shear phases of niobium oxide have shown unprecedented high-rate performance as high-voltage anodes for lithium-ion batteries. The electronic structure, lithium insertion mechanism, and lithium dynamics of these compounds remain relatively unexplored, largely due to their novelty and complexity. I will present our recent work on the electronic structure and lithium transport mechanism of crystallographic shear phases in the Wadsley-Roth family, including mixed-metal TiO2-Nb2O5, and WO3-Nb2O5 phases. These compounds feature blocks of niobium-oxygen octahedra as structural units, and we show that this block structure leads to a coexistence of flat and dispersive energy bands, corresponding to localized and delocalized electronic states. Our work has explored interesting electron localisation-delocalisation transitions on n-type doping in the niobium suboxides, and provides a unified mechanistic picture for the structural changes in the entire family of crystallographic shear phases.

I endeavour to make the presentation interesting for both an electronic structure theory, and a lithium-ion battery perspective.
Date: 26 February 2021, 14:00
Venue: Zoom Link: https://us02web.zoom.us/j/82957737618?pwd=cnkwVGZyYmV6c3lDMm9nVUJvVHkzUT09
Speaker: Andrew Morris
Organising department: Department of Materials
Organiser: Dr Joseph Prentice (University of Oxford)
Organiser contact email address: samantha.pearce@materials.ox.ac.uk
Part of: Oxford Advanced Materials Network
Booking required?: Not required
Audience: Members of the University only
Editor: Samantha Pearce