Dielectric and tunable properties of Zr doped BST ceramics prepared by spark plasma sintering

Zr doped Ba0.6Sr0.4TiO3 ceramic was sintered by spark plasma sintering (SPS) and thermal treatment. Sintering behavior, microstructure and dielectric properties of the BST ceramics were investigated by XRD, SEM and impedance analyzer. High dense Ba0.6Sr0.4(Zr0.2Ti0.8)O3 ceramic with 98.2% of the theoretical density was fabricated at 1270 °C for 5 min. The dielectric constant of this sample reduced to 850 at 100 kHz, the tunability of the ceramic increased to 57% (1.5 kV/mm, 298 K) and the figure of merit (FOM) value increased to 475, which is promising material for tunable devices application.

► Zr doped Ba0.6Sr0.4TiO3 ceramics were sintered by spark plasma sintering (SPS) and thermal treatment.
► The high dense Ba0.6Sr0.4(Zr0.2Ti0.8)O3 ceramic with 98.23% of the theoretical density was fabricated at 1270 °C for 5 min.
► The dielectric constant of Ba0.6Sr0.4(Zr0.2Ti0.8)O3 ceramic reduced to 850 at the frequency of 100 kHz.
► The tunability and the FOM value increased to 57% and 475 (1.5 kV/mm, 298 K).