Skip to content
Research Article Open access CC BY 4.0

Synthesis of Polar Dielectric Barium Magnesium Niobate at Low Sintering Temperature: Dielectric Relaxation and AC Conductivity Study

K. N. Singh, P. K. Bajpai

Physical Science International Journal · pp. 1–13 · Published 27 Oct 2017

10.9734/PSIJ/2017/37111

Abstract

Ba(Mg1/3Nb2/3)O3 is an important microwave polar dielectric material. However, the large leakage current and losses due to defects incorporated during high temperature processing restricts its use in microwave devices. We have synthesized phase pure perovskite Ba(Mg1/3Nb2/3)O3 by controlling the cooling rates during calcination and sintering, using two stage columbite method at relatively low sintering of 1150°C. X-ray diffraction has been used to determine the structural details. Ceramics stabilizes in hexagonal perovskite structure with lattice constant a=5.7803A˚, c=7.0780A˚. Sintered ceramics with density > 93% exhibit surface morphology having homogeneous grain distribution with average grain size is ≈1.0-2.0 mm. Temperature and frequency dependent dielectric response has been analyzed to understand the dielectric dispersion. Dielectric response is temperature independent up to ≈180°C. Beyond this temperature dielectric dispersion is observed which is more pronounced at lower frequencies and associated with significant electrical conductivity. Impedance spectroscopic formalism has been used to separate out the contributions from gains and grain boundary using equivalent circuit approach, whereas, electrical modulus approach has revealed the role of conductivity relaxation. The frequency/ temperature dependent ac conductivity suggests conduction being thermally activated process. AC conduction activation energies are estimated from Arrhenius plots and conduction mechanism is discussed.  

Dielectric relaxation polar dielectrics X-ray diffraction impedance analysis

References (20)

  1. 1 The ‘universal’ dielectric response [DOI]
  2. 2 Impedance and dielectric spectroscopy revisited: Distinguishing localized relaxation from long-range conductivity [DOI]
  3. 3 Electric modulus and interfacial polarization in composite polymeric systems [DOI]
  4. 4 Characterization of Electrical Materials, Especially Ferroelectrics, by Impedance Spectroscopy [DOI]
  5. 5 Impedance Spectroscopy of Undoped BaTiO 3 Ceramics [DOI]
  6. 6 Anomalous conductivity prefactors in fast ion conductors [DOI]
  7. 7 Ceramics for microwave dielectric resonator [DOI]
  8. 8 The polarization of mixed conducting SOFC cathodes: Effects of surface reaction coefficient, ionic conductivity and geometry [DOI]
  9. 9 Ba(Mg1/3Ta2/3)O3 Ceramics with Temperature-Stable High Dielectric Constant and Low Microwave Loss [DOI]
  10. 10 Microwave Loss Quality of BaZn 13 Ta 2/3 O 3 Ceramics [DOI]
  11. 11 Estimation of the free-charge-carrier concentration in fast-ion conducting Na2 S- B2 S3 glasses from an analysis of the frequency-dependent conductivity [DOI]
  12. 12 Effect of simultaneous substitution of Li+ and Ti4+ in ceramics of Pb2KNb5O15 on structure, dielectric, modulus, impedance and conductivity properties [DOI]
  13. 13 Microstructure and Dielectric Properties of Barium Strontium Magnesium Niobate [DOI]
  14. 14 Ionic conduction due to oxygen diffusion in La0.8Sr0.2GaO3−δ electrolyte [DOI]
  15. 15 Synthesis, characterization and dielectric relaxation of phase pure columbite MgNb2O6: Optimization of calcination and sintering [DOI]
  16. 16 Relaxor behavior and dielectric relaxation in Pb(Ba1/3Nb2/3)O3: A phase pure new relaxor material [DOI]
  17. 17 Near-Debye dielectric responses [DOI]
  18. 18 Dielectric ceramics with relaxors and a tetragonal tungsten bronze [DOI]
  19. 19 Order-disorder and dielectric relaxation in SrFeO3−x [DOI]
  20. 20 Dielectric relaxation and ac conductivity study in SrMg1/3Nb2/3O3

Cited by 1

Local Symmetry Reduction in Lanthanum Substituted Barium Stannate Ceramics Densified Using Bi2O3 Sintering Aids

Sharmila Bajpai, P. K. Bajpai · Journal of Electronic Materials · 2019

Related research

Article metrics

Real usage data collected on this platform.

5

Page views

0

PDF downloads

0

Outbound clicks

1

Citations

Views over time

Views by country

Approximate, from request IP at view time — not citizenship or institution. Countries with fewer than 5 views are grouped as "Other".

Traffic sources

Referring site, by host.

Views and downloads exclude known bots/crawlers. Citations combines this platform's own DOI-resolved index with each external source's own reported total — see Cited by above for individually listed citing works. Last refreshed 0 seconds ago.