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Advances in Materials Science and Engineering
Volume 2014, Article ID 602504, 7 pages
http://dx.doi.org/10.1155/2014/602504
Research Article

Effect of Na Content on the Physical Properties of Powders

1Center of Excellence on Catalysis and Catalytic Reaction Engineering, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand
2Department of Chemical Engineering, Faculty of Engineering, Burapha University, Chonburi 20131, Thailand
3Department of Electrical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand

Received 29 May 2013; Accepted 26 November 2013; Published 30 January 2014

Academic Editor: Jun Liu

Copyright © 2014 Tassanee Tubchareon et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The different Na contents (0 ≤ Na ≤ 0.35, based on mole of NaOH) of doped Ba0.5Sr0.5TiO3 (BST) powders synthesized via sol-gel process were studied. The substitution of Na+ ions into a partial A-site of BST powders provided the reduction in vacancy defects as confirmed by electron paramagnetic resonance (EPR) and UV-visible spectroscopy. Photoluminescence (PL) spectra appeared in violet, blue, and green emissions. The phase structure, oxygen deficiency, and titanium deficiency of BST powders were further investigated as a function of Na content. X-ray diffraction (XRD) result was found that low Na content (0 ≤ Na ≤ 0.15) exhibited the tetragonal structure, while it was transformed to the cubic phase when high Na content. Moreover, X-ray photoelectron spectroscopy (XPS) result revealed that the partial oxidation of Ti3+ ions to Ti4+ ions was observed at Na content lower than 0.05 mole, while more addition of Na content resulted in the increasing of the oxygen and the titanium deficiency. Furthermore, the result indicated the oxygen deficiency significantly formed at the A-site of Sr atoms more than that of Ba atoms.