najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМОnajo-1108Research ArticleCHEMISTRY AND MATERIALS SCIENCEХИМИЯ И НАУКА О МАТЕРИАЛАХSynthesis and studies room temperature conductivity, dielectric analysis of LaF3 nanocrystalsSynthesis and studies room temperature conductivity, dielectric analysis of LaF3 nanocrystalsGaurkhedeSidheshwar G.GaurkhedeSidheshwar G.

Sidheshwar G. Gaurkhede

Department of Physics

400058; Andheri (W); Mumbai

Sidheshwar G. Gaurkhede

Department of Physics

400058; Andheri (W); Mumbai

s.gaurkhede@gmail.comBhavan’s College of ASCBhavan’s College of ASC20141708202556843848Copyright © Gaurkhede S.G., 20252025Gaurkhede S.G.Gaurkhede S.G.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/1108

   Lanthanum fluoride (LaF3) was synthesized using LaCl3 and NH4F as starting materials in de-ionized water as solvent via a microwave-assisted technique. The structure of LaF3 nanocrystals, analyzed by XRD and TEM, was found to be hexagonal with an average crystalline particle size of 20 nm (JCPDS standard card (32-0483) of pure hexagonal LaF3 crystals). The resistivity and conductivity at room temperature for LaF3 was verified and found to depend on the applied DC field. At an applied voltage of 20 V/cm – 30 V/cm, the resistivity and conductivity changes rapidly due to the liberation of extra fluoride (F−) ions, whereas the conductivity of LaF3 nanocrystals depends upon temperature. The variation of dielectric constant (ε′) and dielectric loss (ε′′) with applied frequency shows normal dielectric behavior, attributable to the space charge formation. The observed peak in the plot of tangent loss (tan δ) vs. log F around 2.6 KHz can be attributed to interface charge relaxation at the grain boundaries.

   Lanthanum fluoride (LaF3) was synthesized using LaCl3 and NH4F as starting materials in de-ionized water as solvent via a microwave-assisted technique. The structure of LaF3 nanocrystals, analyzed by XRD and TEM, was found to be hexagonal with an average crystalline particle size of 20 nm (JCPDS standard card (32-0483) of pure hexagonal LaF3 crystals). The resistivity and conductivity at room temperature for LaF3 was verified and found to depend on the applied DC field. At an applied voltage of 20 V/cm – 30 V/cm, the resistivity and conductivity changes rapidly due to the liberation of extra fluoride (F−) ions, whereas the conductivity of LaF3 nanocrystals depends upon temperature. The variation of dielectric constant (ε′) and dielectric loss (ε′′) with applied frequency shows normal dielectric behavior, attributable to the space charge formation. The observed peak in the plot of tangent loss (tan δ) vs. log F around 2.6 KHz can be attributed to interface charge relaxation at the grain boundaries.

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