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The polycrystalline sample of LiSr2Nb5O15 (LSN) was prepared by a high-temperature solid state reaction technique. The impedance parameters were studied using an impedance analyzer in a wide range of frequencies (102-106 Hz) at different temperatures (28-500 ℃). Nyquist plot reveals the presence of bulk effect only. The bulk resistance of the compound decreases with rise in temperature which shows the negative temperature coefficient of resistance (NTCR) like a semiconductor. The ac conductivity spectrum was found to obey Jonscher's universal power law. DC conductivity (bulk) with temperature demonstrates that the compound exhibits Arrhenius type of electrical conductivity and the activation energy found to be 0.97 eV.


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Complex impedance properties of LiSr2Nb5O15 ceramic

Show Author's information N.K. MOHANTYaS.K. SATPATHYaBanarji BEHERAa( )P. NAYAKaR.N.P. CHOUDHARYb
School of Physics, Materials Research Laboratory, Sambalpur University, Jyoti Vihar, Burla-768 019, Odisha, India
Department of Physics, ITER, S.O.A. University, Bhubaneswar-751 030, Odisha, India

Abstract

The polycrystalline sample of LiSr2Nb5O15 (LSN) was prepared by a high-temperature solid state reaction technique. The impedance parameters were studied using an impedance analyzer in a wide range of frequencies (102-106 Hz) at different temperatures (28-500 ℃). Nyquist plot reveals the presence of bulk effect only. The bulk resistance of the compound decreases with rise in temperature which shows the negative temperature coefficient of resistance (NTCR) like a semiconductor. The ac conductivity spectrum was found to obey Jonscher's universal power law. DC conductivity (bulk) with temperature demonstrates that the compound exhibits Arrhenius type of electrical conductivity and the activation energy found to be 0.97 eV.

Keywords:

Key words: niobates, conductivity, complex impedance, modulus
Received: 20 August 2012 Accepted: 04 October 2012 Published: 11 December 2012 Issue date: September 2012
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Publication history

Received: 20 August 2012
Accepted: 04 October 2012
Published: 11 December 2012
Issue date: September 2012

Copyright

© The author(s) 2012

Acknowledgements

The authors (PN and BB) acknowledge the financial support through DRS-I under SAP of UGC for the development of research work in the School of Physics, SU.

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