Structural Disorder in Doped Zirconias, Part II: Vacancy Ordering Effects and the Conductivity Maximum
Journal article, 2011
Polarizable interaction potentials, parametrized using ab initio electronic structure calculations, have been used in molecular dynamics simulations to study the conduction mechanism in doped zirconias. The influence of vacancy-vacancy and vacancy-cation interactions on the conductivity of these materials has been characterized. Although the latter can be minimized by using dopant Cations with radii which match those of Zr4+ (as in the case of Sc3+), the former appears as an intrinsic characteristic of the fluorite lattice that cannot be avoided and that is shown to be responsible for the occurrence of a maximum in the conductivity at dopant concentrations between 8 and 13%. The weakness of the Sc-vacancy interactions in Sc2O3-dope zirconia confirms that this material is likely to present the highest conductivity achievable in zirconias.
transport
oxide
construction
inorganic solids and ceramics
ionic conductors
oxygen diffusion
solid oxide fuel cells
yttria-stabilized zirconia
ionic-conductivity
0-less-than-or-equal-to-x-less-than-or-equal-to-1 system
mechanism
molecular-dynamics
theory and modeling
computer-simulation
Author
Dario Marrocchelli
Massachusetts Institute of Technology
University of Edinburgh
Paul Madden
University of Oxford
Stefan Norberg
Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry
S. Hull
ISIS Facility
Chemistry of Materials
0897-4756 (ISSN) 1520-5002 (eISSN)
Vol. 23 6 1365-1373Subject Categories (SSIF 2011)
Physical Chemistry
DOI
10.1021/cm102809t