An ultra-broad working temperature dielectric material obtained with Praseodymium doped BaTiO3–(Bi0.5Na0.5)TiO3–Nb2O5 based ceramics

Abstract A material with stable permittivity (the capacitance is within ±15% of room temperature capacitance) at an ultra-broad temperature range of −55–300 °C has been achieved by doping appropriate amount (mol%) of Pr 6 O 11 in multicomponent BaTiO 3 –(Bi 0.5 Na 0.5 )TiO 3 –Nb 2 O 5 based ceramics. A remarkable high ceiling working temperature of 300 °C has been achieved by the doping of Pr 6 O 11 . It played a crucial role in the stability of high-temperature dielectric properties. While increasing the doping content of Pr 6 O 11 , the dielectric constant was decreased significantly at the temperature range of 200–300 °C and the maximum TCC value was reduced from 39% to only 4%. XRD results showed the substitution of Pr ion appeared in both Ba-site and Ti-site. The substitution decreased the spontaneous polarization of BaTiO 3 and then weakened the ferroelectricity of BaTiO 3 . As a result, the temperature stability of samples was improved obviously. Besides, Pr 6 O 11 addition promoted the formation of sheet grains, which were consisting of BaTi 4 O 9 . The best dielectric and electrical properties ( e r =1608, tan δ =1.54%, ρ V =2.15×10 12 Ω cm) at room temperature appear in the sample with 0.6 mol% Pr 6 O 11 addition.