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http://dx.doi.org/10.4313/JKEM.2011.24.9.723

Enhancement of PTCR Characteristics of MnO2 Doped Lead Free BaTiO3-(Bi0.5Na0.5)TiO3 Ceramics with High Tc (>165℃)  

Kim, Kyoung-Bum (Optic and Electronic Ceramics Division, Korea Institute of Ceramic Engineering & Technology)
Jang, Young-Ho (Optic and Electronic Ceramics Division, Korea Institute of Ceramic Engineering & Technology)
Kim, Chang-Il (Optic and Electronic Ceramics Division, Korea Institute of Ceramic Engineering & Technology)
Jeong, Young-Hun (Optic and Electronic Ceramics Division, Korea Institute of Ceramic Engineering & Technology)
Lee, Young-Jin (Optic and Electronic Ceramics Division, Korea Institute of Ceramic Engineering & Technology)
Paik, Jong-Hoo (Optic and Electronic Ceramics Division, Korea Institute of Ceramic Engineering & Technology)
Lee, Woo-Young (HIEL Corporation)
Kim, Dae-Joon (HIEL Corporation)
Publication Information
Journal of the Korean Institute of Electrical and Electronic Material Engineers / v.24, no.9, 2011 , pp. 723-727 More about this Journal
Abstract
0.935Ba$TiO_3$-0.065($Bi_{0.5}Na_{0.5}$)$TiO_3+xmol%MnO_2$ (BBNTM-x) ceramics with $0{\leq}x{\leq}0.05$ were fabricated with muffled sintering by a modified synthesis process. Their microstructure and enhanced positive temperature coefficient of resistivity (PTCR) characteristics were systematically investigated in order to obtain lead-free high TC PTCR thermistors. All specimens showed a perovskite structure with a tetragonal symmetry and no secondary phase was observed. Grain growth was achieved when the doped MnO2 was increased above 0.02 mol%. This is due to the effect of positive Mn ion doping as an acceptor compensating a Ba vacancy occurred by the higher donor dopant concentration of $Bi^{3+}$ ion. Especially, enhanced PTCR characteristics of the extremely low ${\rho}_{RT}$ of $9\;{\Omega}{\cdot}cm$, PTCR jump of $5.1{\times}10^3$, ${\alpha}$ of 15.5%/$^{\circ}C$ and high $T_C$ of $167^{\circ}C$ were achieved for the BBNTM-0.04 ceramics.
Keywords
PTCR; Lead-free; $(Bi_{0.5}Na_{0.5})TiO_3$; Thermistor; Modified synthesis;
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1 M. L. Liu, Y. F. Qu, and D. A. Yang, J. Alloys. Comp., 503, 237 (2010).   DOI
2 O. Saburi, J. Phys. Soc. Jpn., 14, 1174 (1959).   DOI
3 W. Huo and Y. Qu, Sensor. Actuat. A-phys., 128, 265 (2006).   DOI
4 T. Shimada, K. Touji, Y. Katsuyama, H. Takeda, and T. Shiosaki, J. Eur. Ceram. Soc., 27, 3877 (2007).   DOI
5 H. Takeda, T. Shimada, Y. Katsuyama, and T. Shiosaki, J. Electroceram., 22, 269 (2009).
6 H. Takeda, W. Aoto, and T. Shiosaki, Appl. Phys. Lett., 87, 102104 (2005).   DOI
7 J. Wei, W. Pu, Y. Mao, and J. Wang, J. Am. Ceram. Soc., 93, 1527 (2010).
8 J. Wei, Y. Pu, Y. Mao, and H. Wu, J. Mater. Sci., 22, 551 (2011).
9 Y. Pu, J. Wei, Y. Mao, and J. Wang, J. Alloys Compd., 498, 5 (2010).   DOI
10 X. Wang, H. L. Chan, and C, Choy, J. Eur. Ceram. Soc., 24, 1227 (2004).   DOI
11 P. H. Xiang, H. Takeda, and T. Shiosaki, Jpn. J. Appl. Phys., 46, 6995 (2007).   DOI
12 Y. H. Jeong, C. M. Kim, C. I. Kim, Y. S. Cho, Y. J. Lee, J. H. Paik, W. Y. Lee, and D. J. Kim, J. Electricchem. Soc., 158, 27 (2011).