Metal oxides can act as insulators, semiconductors, or metals depending on their chemical composition and crystal structure. Metal oxide semiconductors, which support equilibrium populations of electron and hole charge carriers, have widespread applications including batteries, solar cells, and display technologies. It is often difficult to predict in advance whether these materials will exhibit localized or delocalized charge carriers upon oxidation or reduction. We combine data from first-principles calculations of the electronic structure and dielectric response of 214 metal oxides to predict the energetic driving force for carrier localization and transport. We assess descriptors based on the carrier effective mass, static polaron binding energy, and Fröhlich electron-phonon coupling. Numerical analysis allows us to assign p- and n-type transport of a metal oxide to three classes: (i) band transport with high mobility; (ii) small polaron transport with low mobility; and (iii) intermediate behavior. The results of this classification agree with observations regarding carrier dynamics and lifetimes and are used to predict 10 candidate p-type oxides.
Bibliographical noteFunding Information:
The research was funded by the Royal Society (Grant No. UF130329), the Faraday Institution (Grant No. FIRG003), EPSRC (EP/L01551X/1 and EP/N01572X/1), and the European Research Council, ERC, (Grant No. 758345). We are grateful to the UK Materials and Molecular Modelling Hub for computational resources, which is partially funded by EPSRC (EP/P020194/1). Via our membership of the UK’s HPC Materials Chemistry Consortium, which is funded by EPSRC (EP/L000202, EP/R029431), this work used the ARCHER UK National Supercomputing Service ( http://www.archer.ac.uk ).
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Physical and Theoretical Chemistry