Is ReO3 a mixed ionic–electronic conductor? A DFT study of defect formation and migration in a BVIO3 perovskite-type oxide. Issue 12 (7th March 2018)

• Record Type: Journal Article
• Authors: Parras, J. P.; Genreith-Schriever, A. R.; Zhang, H.; Elm, M. T.; Norby, T.; De Souza, R. A.
• Is Part Of: Physical chemistry chemical physics. Volume 20:Issue 12(2018)
• Page Start: 8008
• Page End: 8015
• Publication Date: 2018-03-07
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c7cp08214b
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Unexpected behaviour of the migration energetics of oxide ions, hydronium ions and lithium ions in perovskite-structured ReO3 . Abstract : Density-functional-theory (DFT) calculations within the generalised gradient approximation (GGA) were used to examine the behaviour of point defects in the cubic B VI O3 perovskite-type oxide, ReO3 . Energies of reduction and of hydration were calculated, and the results are compared with literature data for AB O3 perovskite oxides. The activation energies of migration were determined for O 2−, H +, Li +, Na +, K + and H3 O + . An occupied A site in ReO3 is found to be beneficial to oxide-ion migration by a vacancy mechanism as well as to proton migration by a Grotthuss mechanism. Na +, K + and H3 O + exhibit activation energies of migration higher than 2 eV, whereas Li + is characterised by a very low migration barrier of 0.1 eV. Reasons for this behaviour are discussed. Our results suggest that H +, O 2−, and especially Li +, are highly mobile ions in ReO3 .