Dielectric studies of nanocrystalline calcium tungstate
https://doi.org/10.17586/2220-8054-2016-7-4-599-603
Abstract
Nanocrystalline samples of CaWO4 were prepared at room temperature by simple chemical precipitation. The samples were characterized by X-ray diffraction and scanning electron microscopy. Energy dispersive X-ray analysis confirmed the elements present in the sample. The frequency and temperature dependence of the dielectric constant and ac electrical conductivity of the nanomaterial were investigated. Very low dielectric loss in nanocrystalline CaWO4 powder was observed at high frequencies. The values of ac electrical conductivity calculated from the permittivity studies were found to increase as frequency increased, conforming to small polaron hopping.
Supporting agencies: The authors are indebted to NSRC, Nirmala College, Muvattupuzha and Newman College, Thodupuzha for the support to undertake this study. The financial support from the University Grants Commission, New Delhi, India (FIP/12th Plan/KLMG020 TF03) is greatly acknowledged.
About the Authors
N. Aloysius
Newman College
India
India
Department of Physics
Thodupuzha-685 585, Kerala
M. S. Rintu
Maharajas College
India
India
Department of Physics
Ernakulam-682 011, Kerala
E. M. Muhammed
Maharajas College
India
India
Department of Physics
Ernakulam-682 011, Kerala
T. Varghese
Newman College;
Nirmala College
India
India
Department of Physics, Newman College; Nanoscience Research Centre (NSRC), Department of Physics, Nirmala College
Thodupuzha-685 585, Kerala;
Muvattupuzha – 686 661, Kerala
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Review
For citations:
Aloysius N., Rintu M.S., Muhammed E.M., Varghese T. Dielectric studies of nanocrystalline calcium tungstate. Nanosystems: Physics, Chemistry, Mathematics. 2016;7(4):599-603. https://doi.org/10.17586/2220-8054-2016-7-4-599-603
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