Synthesis of calcium doped strontium barium niobate ceramic samples
G. STANCIU1,2,*
,
A. ACHIM1,
N. D. SCARISOREANU1,
V. ION1,3,
R. BIRJEGA1,
E. ANDRONESCU2,
M. DINESCU1
Affiliation
- National Institute for Lasers, Plasma and Radiation Physics, Magurele, Romania 077125
- University Politehnica of Bucharest, Faculty of Applied Chemistry and Material Science, Bucharest, Romania, 011061
- Faculty of Physics, University of Bucharest, 077125 Magurele, Romania
Abstract
High density polycrystalline SrxBa1-xNb2O6 (SBN) ceramics (with x= 0.50 ÷ 0.60) undoped and Ca doped SBN were obtained by conventional solid-state reaction method. The Ca was used as dopant for increasing the ferroelectric-paralectric transition temperature, as well as for improving the dielectric leaky behavior of pure SBN. The XRD analysis showed that pure SBN phase is crystallized into a tetragonal tungsten bronze (TTB) structure without secondary phase. Ca doped composition shows a small amount of secondary phase of CaNb2O6. SEM micrographs indicate formation of crystallites with sharp boundaries with an average grain size of about 2 ÷ 6 μm for pure SBN ceramics, while for Ca doped SBN the grains size increases up to 10 μm. The dielectric characterization shows high dielectric constant values for SBN:50 and SBN:60. Instead, the Ca doping has the effect on the reduction of dielectric constant value, but the dielectric losses are found to be smaller for this composition..
Keywords
SBN, CBN, SCBN, TTB structure, Ceramic target, Dielectric properties.
Citation
G. STANCIU, A. ACHIM, N. D. SCARISOREANU, V. ION, R. BIRJEGA, E. ANDRONESCU, M. DINESCU, Synthesis of calcium doped strontium barium niobate ceramic samples, Optoelectronics and Advanced Materials - Rapid Communications, 9, 5-6, May-June 2015, pp.720-723 (2015).
Submitted at: April 22, 2015
Accepted at: May 7, 2015