Dielectric studies of nanocrystalline Manganese Tungstate
Abstract
The dielectric properties of monoclinic manganese tungstate have been studied as a function of frequency and temperature. It was found that the dielectric constant and dielectric loss for all temperatures had high values at low frequencies which decreased rapidly as frequency increased attaining a constant value at higher frequencies. The a.c. conductivity increased as frequency increased, conforming small polaron hopping. As temperature increased, the values of the a.c. conductivity are shifted to higher values. Higher values were also obtained when the particle size decreased. These properties make the nano-sized MnWO4 as a promising material for fabricating humidity sensors.
Supporting agencies: The authors are grateful to KSCSTE, Thiruvananthapuram, Kerala and University Grants Commission (UGC), New Delhi for the financial support.
About the Authors
N. Aloysius Sabu
Nanoscience Research Centre (NSRC), Department of Physics, Nirmala College
India
India
Muvattupuzha - 686 661, Kerala
K. P. Priyanka
Nanoscience Research Centre (NSRC), Department of Physics, Nirmala College
India
India
Muvattupuzha - 686 661, Kerala
Smitha Thankachan
Department of Physics, Maharaja’s College
India
India
Ernakulam - 682 011, Kerala
Anu Tresa Sunny
School of Chemical Sciences, MG University
India
India
Kottayam - 686 560, Kerala
E. M. Mohammed
Department of Physics, Maharaja’s College
India
India
Ernakulam - 682 011, Kerala
O. P. Jaseentha
Nanoscience Research Centre (NSRC), Department of Physics, Nirmala College
Russian Federation
Russian Federation
Muvattupuzha - 686 661, Kerala
Thomas Varghese
Nanoscience Research Centre (NSRC), Department of Physics, Nirmala College
India
India
Muvattupuzha - 686 661, Kerala
References
1. E. Traversa, Ceramic sensors for humidity detection: the state of the art and future developments. Sens. Actuators B, 23, P. 135–156 (1995).
2. W. Qu, W. Wlodarski, J.U. Meyer, Comparative study on micromorphology and humidity sensitive properties of thin-film and thick film humidity sensors based on semiconducting MnWO4. Sens. Actuators B, 64, P. 76–82 (2000).
3. A.M.E. Suresh Raj, C. Mallika, O.M. Sreedharan, K.S. Nagaraja, MnO-manganese tungstate composite humidity sensors. Mater. Lett., 53, P. 316–320 (2002).
4. R. Bharati, R.A. Singh, B.M. Wanklyn, Electrical conduction in Manganese Tungstate. J. Phys. Chem. Solids, 43, P. 641–644 (1982).
5. S.J. Chen, X.T. Chen, Z. Xue, J.H. Zhou, J. Li, Morphology control of MnWO4 nanocrystals by a solvothermal route. J. Mater. Chem., 13, P. 1132–1135 (2003).
6. B. Parvatheeswara Rao, K.H. Rao, Electrical properties of nanocrystalline AlPO4. J. Mater. Sci., 32, P. 6049–6054 (1997).
7. C.M. Mo, L. Zhang, G. Wang, Characteristics of dielectric behavior in nanostructured materials Nanostruct. Mater., 6, P. 823–826 (1995).
8. T. Kar, R. N. Choudhary, S. Sharma, K. S. Singh, Structural and electrical properties of Ba2Na3RNb10O30 Ceramics. Indian J. Phys, 73A(4), P. 453–459 (1999).
9. B. Jiang, J.L. Peng, L.A. Busil,W.L. Zhong, Size effects on ferroelectricity of ultrafine particles of PbTiO3. J. Appl. Phys., 87(7), P. 3462–3467 (2000).
10. D.Ravinder, K.Vijayakumar, Dielectric behaviour of erbium substituted Mn–Zn ferrites. Bull. Mater. Sci., 24(5), P. 505–509 (2001).
11. S.N. Potty, M.A. Khader, Dielectric Properties of nanophase Ag2HgI4 and Ag2HgI4-Al2O3 nanocom-posites. Bull. Mater. Sci., 23(5), P. 361–367 (2000).
12. J. Mathew, S. Kurien, S. Sebastian, K.C. George, Dielectric studies of nanocrystalline copper orthophosphate. Ind. J. Phys., 78(9), P. 947–950 (2004).
13. V. Murthy, K. Sobhanadri, Dielectric properties of some nickel-zinc ferrites at radio frequency. Phys Status Solidi (a), 36, P. K133 (1976).
14. M.A.K.L. Dissanayake, O.A. Ileperuma, P.A.G.D. Darmasena, AC conductivity of MnWO4. J. Phys. Chem. Solids, 50, P. 359–361 (1989).
15. R. Shukla, Electrical properties of AgInTe2. Ind. J. Pure Appl. Phys., 31, P. 894–898 (1993).
Review
For citations:
Aloysius Sabu N., Priyanka K.P., Thankachan S., Sunny A.T., Mohammed E.M., Jaseentha O.P., Varghese T. Dielectric studies of nanocrystalline Manganese Tungstate. Nanosystems: Physics, Chemistry, Mathematics. 2013;4(3):357-362.
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