Journal
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
Volume 72, Issue 1, Pages 17-23Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.jpcs.2010.10.016
Keywords
Ceramics; Nanostructures; Raman spectroscopy; X-ray diffraction; Dielectric properties
Ask authors/readers for more resources
BaTiO3-x and Ba0.95La0.05TiO3-x nanoceramics showing colossal permittivity values have been characterized. While starting powders are of cubic symmetry, X-ray and Neutron Diffraction techniques and Raman Spectroscopy measurements show that the one-step processed ceramics obtained by Spark Plasma Sintering (SPS) contain cubic and tetragonal phases. Rather large oxygen deficiency determined in such ceramics by Electron Micro Probe analysis and Electron Energy Loss Spectroscopy analyzes is explained by the presence of Ti3+, as evidenced by X-ray Photoelectron Spectroscopy measurements. Transmission Electron Microscopy and High Resolution Transmission Electron Microscopy show that these ceramics contain 50-300 nm grains, which have single-domains, while grain boundaries are of nanometer scale. Colossal permittivity values measured in our dense nanoceramics are explained by a charge hopping mechanism and an interfacial polarization of a large number of polarons generated after sample reduction in SPS apparatus. (C) 2010 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available