Effect of ionic substitution on the structural, dielectric and electrical properties of bismuth zinc niobate ceramics


Qasrawi A. F. , Abu Je'ib H. A. , Mergen A.

JOURNAL OF CERAMIC PROCESSING RESEARCH, cilt.13, sa.4, ss.446-450, 2012 (SCI İndekslerine Giren Dergi) identifier

  • Cilt numarası: 13 Konu: 4
  • Basım Tarihi: 2012
  • Dergi Adı: JOURNAL OF CERAMIC PROCESSING RESEARCH
  • Sayfa Sayıları: ss.446-450

Özet

The effects of tin substitution on the structural, dielectric and electrical properties of the Bi1.5Zn0.92Nb1.5O6.92 pyrochlore ceramics have been investigated. Tin atoms was substituted in the A (Bi1.5Zn0.46)-site instead of zinc and in the B ((Zn0.46Nb1.5)-site instead of niobium in accordance to the chemical formulae Bi1.5Zn0.92Nb1.5-xO6.92-x/2 and (Bi1.5-x/3Zn0.46-3x/2Snx)(Nb1.5Zn0.46)O-6.92, for 0.00 <= x <= 0.40 and 0.00 <= x <= 0.60, respectively. A relative single phase formation of the structures was possible for x values less than 0.25 and less than 0.10. Pronounced tunability in the dielectric constant values associated with very low dielectric loss are obtainable by Sn substitution. Furthermore, a frequency invariant but linearly varying temperature dependent dielectric constant is observed. The electrical conductivity decreased by two and one order of magnitude for the A and B-site substitutions, respectively. The temperature-dependent conductivity analysis in the temperature region of 300-500 K, reflected the existence of shallow and deep impurity energy levels being created by the doping process.