Synthesis, Phase Evolutions, and Properties of the Perovskite Ba6Ca2Ti2Nb3O19.5

Authors：Pan, Zh.^*; Wei, H.; Xu, J.; Fang, L.; Kuang, X.

Source：Journal of Ceramic Science and Technology, 2023, 14(1).

DOI：10.4416/JCST2022-00013

• 5
• simple cubic perovskite
• B-site disorder
• high permittivity
• alternating current impedance

In the present study, Ba6Ca2Ti2Nb2+xO17+2.5x (BCTN, x & LE; 1.0) materials were synthesized with the traditional solid-state reaction method. The phase evolution, structure, relative permittivity, and electrical conduction prop-erties of these materials were studied. The results revealed that increasing the Nb content and improving the cal-cining temperature favored the formation of a pure simple cubic perovskite structure. For the end member of Ba6Ca2Ti2Nb2+xO17+2.5x, i.e. Ba6Ca2Ti2Nb3O19.5, Rietveld structural refinement disclosed that about 25 % Ca ions and all the Ba ions occupied the A site, while the remaining cations were disordered and occupied the B site. Thus, it can also be written as (Ba6Ca0.5)(Ca1.5Ti2Nb3)O19.5. This material exhibited high permittivity up to 80 and the electrical conductivity was 1.33x10-4 S/cm at 800 & DEG;C which was dominated by electronic conduction.

• Institution
  广西大学; 桂林理工大学