hide
Free keywords:
-
Abstract:
The lattice parameter of nanocrystalline ceria films prepared by
sputtering was monitored as a function of annealing temperature. Within
the temperature range of 150-420 degrees C, an equilibrium with
atmospheric oxygen is established within a few hours, whereas grain
growth does not occur. On the basis of the experimental results and
analysis of literature data, we present a model that posits the
formation of a non-uniform grain structure with stoichiometric
interiors and oxygen deficient boundaries. This model, based on defect
thermodynamics, correctly describes the dependence of the lattice
parameter of nanocrystalline ceria on annealing temperature and grain
size and can be extended to other materials as well.
