Paper Type |
Contributed Paper |
Title |
Study on Electrical Properties of Mn-doped 6h-BaTiO3 Ceramics Using Impedance Spectroscopy |
Author |
Neungreuthai Phoosit and Sukon Phanichphant |
Email |
sphanichphant@yahoo.com |
Abstract:
The hexagonal polymorph of BaTiO3 (P63/mmc) was stabilised at room temperature by partial replacement of Ti with Mn, where Ba(Ti1-xMnx)O3 (0.05d” x d”0.3) was prepared from mixed oxide route at 1,250ºC. The phase-purity and lattice parameters of calcined powders and sintered pellets were examined by X–ray diffraction (XRD) using the index scheme for undoped 6h- BaTiO3 (reported in the ICDD file number 82-1175 as space group P63/mmc with lattice parameters of a = 5.72380(70) Å, c = 13.96490(70) Å, V = 396.2 Å3). The average grain size of samples was measured and found to be 5-50 µm in width and 8-120 µm in length for Ba(Ti0.95Mn0.05)O3 , 3-5 µm for Ba(Ti0.90Mn0.10)O3, 4-6 µm for Ba(Ti0.80Mn0.20)O3 and 3-6 µm for Ba(Ti0.70Mn0.30)O3 The impedance measurements were conducted at . 300–500°C, in the frequency range from 5 Hz to 13 MHz, to separate grain and grain boundary contributions. The grain and grain boundaries relaxation frequencies were shifted to higher frequency with increasing temperature. Bulk resistance of Mn-doped BaTiO3 ceramics was 2.32×105 Ωcm for Ba(Ti0.95Mn0.05)O3, 1.04×106Ωcm for Ba(Ti0.90Mn0.10)O3, 2.46×105Ωcm for Ba(Ti0.80Mn0.20)O3 and 10709 Ωcm for Ba(Ti0.70Mn0.30)O3 Single grain boundary resistance .indicated that grain boundary resistance increased with acceptor doping. Activation energies were calculated to be in the range of 0.651-0.851 eV.
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Start & End Page |
297 - 308 |
Received Date |
2007-06-11 |
Revised Date |
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Accepted Date |
2007-07-03 |
Full Text |
Download |
Keyword |
6h-BaTiO3, Mn doped BaTiO3, impedance spectroscopy, grain, grain boundary |
Volume |
Vol.34 No.3 (SEPTEMBER 2007) |
DOI |
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Citation |
Phoosit N. and Phanichphant S., Study on Electrical Properties of Mn-doped 6h-BaTiO3 Ceramics Using Impedance Spectroscopy, Chiang Mai J. Sci., 2007; 34(3): 297-308. |
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