Journal Home > Volume 2 , issue 2

The polycrystalline samples of complex tungsten bronze (TB) Na2Pb2R2W2Ti4V4O30 (R=Dy, Pr) compounds were prepared by solid-state reaction technique. Room- temperature preliminary structural studies confirm the formation of the compounds in the orthorhombic crystal system. Detailed studies of electrical properties of the materials using complex impedance spectroscopy technique exhibit that the impedance and related parameters are strongly dependent upon temperature and microstructure (bulk, grain boundary, etc). An observation of negative temperature coefficient of resistance (NTCR) suggests the materials have semiconducting properties. The variation of AC conductivity with temperature shows a typical Arrhenius behavior of the materials. Both the samples obey Jonscher’s universal power law. The existence of hopping mechanism in the electrical transport processes in the system with non-exponential type of conductivity relaxation is confirmed by electrical modulus analysis.


menu
Abstract
Full text
Outline
About this article

Electrical properties of Na2Pb2R2W2Ti4V4O30 (R = Dy, Pr) ceramics

Show Author's information Piyush R. DAS*( )B. N. PARIDAR. PADHEER. N. P. CHOUDHARY
Department of Physics, Institute of Technical Education & Research, Siksha ‘O’ Anusandahan University, Khandagiri, Bhubaneswar 751030, Odisha, India

Abstract

The polycrystalline samples of complex tungsten bronze (TB) Na2Pb2R2W2Ti4V4O30 (R=Dy, Pr) compounds were prepared by solid-state reaction technique. Room- temperature preliminary structural studies confirm the formation of the compounds in the orthorhombic crystal system. Detailed studies of electrical properties of the materials using complex impedance spectroscopy technique exhibit that the impedance and related parameters are strongly dependent upon temperature and microstructure (bulk, grain boundary, etc). An observation of negative temperature coefficient of resistance (NTCR) suggests the materials have semiconducting properties. The variation of AC conductivity with temperature shows a typical Arrhenius behavior of the materials. Both the samples obey Jonscher’s universal power law. The existence of hopping mechanism in the electrical transport processes in the system with non-exponential type of conductivity relaxation is confirmed by electrical modulus analysis.

Keywords:

ceramics, impedance spectroscopy, electrical properties, ferroelectricity, microstructure
Received: 11 January 2013 Revised: 06 February 2013 Accepted: 16 February 2013 Published: 04 June 2013 Issue date: June 2013
References(27)
[1]
Singh AK, Choudhary RNP. Study of ferroelectric phase transition in Pb3R3Ti5Nb5O30 (R = rare earth ion) ceramics. Ferroelectrics 2005, 325: 7–14.
[2]
Kim MS, Lee JH, Kim JJ, et al. Microstructure evolution and dielectric properties of Ba5-xNa2xNb10O30 ceramics with different Ba–Na ratios. J Solid State Electr 2006, 10: 18–23.
[3]
Fang L, Zhang H, Huang TH, et al. Preparation, structural, and dielectric properties of Ba5YZnM9O30 (M = Nb, Ta) ceramics. J Mater Sci 2005, 40: 533–535.
[4]
Behera B, Nayak P, Choudhary RNP. Structural, dielectric and electrical properties of NaBa2X5O15 (X = Nb and Ta) ceramics. Mater Lett 2005, 59: 3489–3493.
[5]
Hornebecq V, Elissalde C, Reau JM, et al. Relaxations in new ferroelectric tantalates with tetragonal tungsten bronze structure. Ferroelectrics 2000, 238: 57–63.
[6]
Ganguly P, Jha AK, Deori KL. Complex impedance studies of tungsten–bronze structured Ba5SmTi3Nb7O30 ferroelectric ceramics. Solid State Commun 2008, 146: 472–477.
[7]
Neurgaonkar RR, Nelson JG, Oliver JR, et al. Ferroelectric and structural properties of the tungsten bronze system K2Ln3+Nb5O15, Ln = La to Lu. Mater Res Bull 1990, 25: 959–970.
[8]
Fang L, Zhang H, Yang JF, et al. Preparation, characterization and dielectric properties of Ba5LnZnTa9O30 (Ln = La, Sm) ceramics. Matet Res Bull 2004, 39: 677–682.
[9]
Qu YQ, Li AD, Shao QY, et al. Structure and electrical properties of strontium barium niobate ceramics. Mater Res Bull 2002, 37: 503–513.
[10]
Das PR, Biswal L, Behera B, et al. Structural and electrical properties of Na2Pb2Eu2W2Ti4X4O30 (X = Nb, Ta) ferroelectric ceramics. Mater Res Bull 2009, 44: 1214–1218.
[11]
Das PR, Choudhary RNP, Samantray BK. Diffuse ferroelectric phase transition in Na2Pb2Sm2W2Ti4Nb4O30 ceramics. Mater Chem Phys 2007, 101: 228–233.
[12]
Das PR, Choudhary RNP, Samantray BK. Diffuse ferroelectric phase transition in Na2Pb2Nd2W2Ti4Nb4O30 ceramic. J Alloys Compd 2008, 448: 32–37.
[13]
Das PR, Choudhary RNP, Samantray BK. Diffuse phase transition in Na2Pb2R2W2Ti4V4O30 (R = Gd, Eu) ferroelectric ceramics. J Phys Chem Solids 2007, 68: 516–522.
[14]
Das PR, Behera B, Choudhary RNP, et al. Ferroelectric properties of Na2Pb2R2W2Ti4V4O30 (R = Dy, Pr) ceramics. Res Lett Mater Sci 2007, Article ID: 91796.
[15]
Wu E. POWDMULT—An interactive powder diffraction data interpretation and indexing program, Version 2.5. Bedford Park, Australia: School of Physical Science, Finders University of South Australia.
[16]
Plocharski J, Wieczoreck W. PEO based composite solid electrolyte containing nasicon. Solid State Ionics 1988, 28–30: 979–982.
[17]
Behera B, Nayak P, Choudhary RNP. Structural and impedance properties of KBa2V5O15 ceramics. Mater Res Bull 2008, 43: 401–410.
[18]
Jonscher AK. The ‘universal’ dielectric response. Nature 1977, 267: 673–679.
[19]
Suman CK, Prasad K, Choudhary RNP. Complex impedance studies on tungsten–bronze electroceramic: Pb2Bi3LaTi5O18. J Mater Sci 2006, 41: 369–375.
[20]
Sen S, Choudhary RNP, Pramanik P. Structural and electrical properties of Ca2+-modified PZT electroceramics. Physica B 2007, 387: 56–62.
[21]
Behera B, Nayak P, Choudhary RNP. Impedance spectroscopy study of NaBa2V5O15 ceramic. J Alloys Compd 2007, 436: 226–232.
[22]
Das PS, Chakraborty PK, Behera B, et al. Electrical properties of Li2BiV5O15 ceramics. Physica B 2007, 395: 98–103.
[23]
Sinclair DC, West AR. Impedance and modulus spectroscopy of semiconducting BaTiO3 showing positive temperature coefficient of resistance. J Appl Phys 1989, 66: 3850–3856.
[24]
Hodge IM, Ingram MD, West AR. A new method for analysing the a.c. behaviour of polycrystalline solid electrolyte. J Electroanal Chem Interfacial Electroch 1975, 58: 429–432.
[25]
Saha S, Sihna TP. Low-temperature scaling behavior of BaFe0.5Nb0.5O3. Phys Rev B 2002, 65: 134103.
[26]
Jonscher AK. Universal Relaxation Law. London: Chelsea Dielectrics Press, 1996.
[27]
Funke K. Jump relaxation in solid electrolytes. Prog Solid State Ch 1993, 22: 111–195.
Publication history
Copyright
Rights and permissions

Publication history

Received: 11 January 2013
Revised: 06 February 2013
Accepted: 16 February 2013
Published: 04 June 2013
Issue date: June 2013

Copyright

© The author(s) 2013

Rights and permissions

Open Access: This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.

Reprints and Permission requests may be sought directly from editorial office.

Return