najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2016-7-4-599-603najo-1244Research ArticleСтатьиDielectric studies of nanocrystalline calcium tungstateDielectric studies of nanocrystalline calcium tungstateAloysiusN.AloysiusN.

Department of Physics

Thodupuzha-685 585, Kerala

Department of Physics

Thodupuzha-685 585, Kerala

nanoncm@gmail.comRintuM. S.RintuM. S.

Department of Physics

Ernakulam-682 011, Kerala

Department of Physics

Ernakulam-682 011, Kerala

MuhammedE. M.MuhammedE. M.

Department of Physics

Ernakulam-682 011, Kerala

Department of Physics

Ernakulam-682 011, Kerala

VargheseT.VargheseT.

Department of Physics, Newman College;   Nanoscience Research Centre (NSRC), Department of Physics, Nirmala College

Thodupuzha-685 585, Kerala;Muvattupuzha – 686 661, Kerala

Department of Physics, Newman College;   Nanoscience Research Centre (NSRC), Department of Physics, Nirmala College

Thodupuzha-685 585, Kerala; Muvattupuzha – 686 661, Kerala

Newman CollegeNewman CollegeMaharajas CollegeMaharajas CollegeNewman College; Nirmala CollegeNewman College; Nirmala College20162208202574599603Copyright © Aloysius N., Rintu M.S., Muhammed E.M., Varghese T., 20252025Aloysius N., Rintu M.S., Muhammed E.M., Varghese T.Aloysius N., Rintu M.S., Muhammed E.M., Varghese T.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://nanojournal.ifmo.ru/jour/article/view/1244

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.

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.

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The authors declare that there are no conflicts of interest present.