Influence of superstructures on rich transport properties of lithium cobaltate

DOI

In the vicinity of x ~ 0.75, LixCoO2 has potential as a thermoelectric, since it has a high Seebeck coefficient and metallic conductivity. We have performed the first successful single-crystal neutron diffraction study of LixCoO2 for x ~ 0.75 and have determined its superstructure. This proposal is to determine the Li ordering for x ~ 0.67, 0.87 and 0.95. There is evidence of charge ordering for x ~ 0.67, and we believe that this is due to a honeycomb lattice of Li ions. The Seebeck coefficient is a maximum in the non-metallic phase at x ~ 0.87, and there is a peak as a function of temperature that is attributed to vacancy disorder. A first order Mott transition is predicted in the semiconducting phase at x ~ 0.95, connected with the Li vacancies. The aim is to correlate the extraordinarily rich transport properties of LixCoO2 at high x with the ordering of the Li ions.

Identifier
DOI https://doi.org/10.5286/ISIS.E.24086422
Metadata Access https://icatisis.esc.rl.ac.uk/oaipmh/request?verb=GetRecord&metadataPrefix=oai_datacite&identifier=oai:icatisis.esc.rl.ac.uk:inv/24086422
Provenance
Creator Dr Matthias Gutmann; Professor Jon Goff; Dr Uthayakumar Sivaperumal; Mr Manoj Soundhira Pandiyan; Dr Michel Roger; Dr Dan Porter; Dr David Voneshen
Publisher ISIS Neutron and Muon Source
Publication Year 2015
Rights CC-BY Attribution 4.0 International; https://creativecommons.org/licenses/by/4.0/
OpenAccess true
Contact isisdata(at)stfc.ac.uk
Representation
Resource Type Dataset
Discipline Photon- and Neutron Geosciences
Temporal Coverage Begin 2011-08-02T09:46:54Z
Temporal Coverage End 2012-07-31T07:41:55Z