High-temperature dielectrics based on (1-y)[(1-x)Bi0.5Na0.5TiO3-xBiAlO3]-yCaZrO3 ternary system with stable permittivity and low dielectric loss in a wide temperature range

Abstract High temperature dielectrics based on (1-y)[(1-x)Bi 0.5 Na 0.5 TiO 3 -xBiAlO 3 ]-yCaZrO 3 (BNT-100xBA-100yCZ) ternary system were designed and prepared. The introduction of BiAlO 3 is verified to create defect dipoles ( A l T i ' - V O • • ) • , which leads to the increase of the resistivity and decrease of dielectric loss in BNT-100xBA-100yCZ at high temperature. And the introduction of CaZrO 3 is helpful to increase the temperature stability of permittivity, which is probably due to an inhomogeneous domain structure. The composition of x=0.09 and y=0.05 has a good overall dielectric properties, with permittivity value of 765 at 25 °C and 1263 at 200 °C, small variance of permittivity (Δe'/e' 200 °C ≤ ±15%) between 133 °C and 500 °C and low dielectric loss (tan ≤ 0.02) in the temperature range of 160 °C ˜425 °C. Therefore, this system will be one of promising candidates of dielectrics used for high-temperature capacitors.