ISSN:
1573-8663
Keywords:
nanocrystals
;
cerium oxide
;
defects
;
interfaces
;
conductivity
;
nonstoichiometry
;
catalysis
Source:
Springer Online Journal Archives 1860-2000
Topics:
Electrical Engineering, Measurement and Control Technology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract We synthesized dense CeO $${2 - x} $$ polycrystals of ∼10 nm grain size and characterized their electrical conductivity, in order to determine whether the defect properties of nanocrystalline solids fundamentally differ from those of conventional materials. The nanocrystals exhibit enhanced electronic conductivity, greatly reduced grain boundary impedance, and a heat of reduction more than 2.4 eV lower per oxygen vacancy compared to their coarse-grained counterparts. We propose that defect formation at low energy grain boundary sites is responsible for these properties, and that nanocrystalline oxides represent bulk materials possessing the defect thermodynamics of interfaces.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1009934829870
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