Abstract
(Ba1-xBi0.67xNa0.33x)(Ti1-xBi0.33xSn0.67x)O3 (abbreviated as BBNTBS, 0.02 ≤ x ≤ 0.12) ceramics were fabricated via a traditional solid state reaction method. The phase transition of BBNTBS from tetragonal to pseudo cubic is demonstrated by XRD and Raman spectra. The BBNTBS (x = 0.1) ceramics have decent properties with a high εr (~2250), small Δε/ε25°C values of ±15% over a wide temperature range from -58 to 171 ℃, and low tanδ ≤ 0.02 from 10 to 200 ℃. The basic mechanisms of conduction and relaxation processes in the high temperature region were thermal activation, and oxygen vacancies might be the ionic charge transport carriers. Meanwhile, BBNTBS (x = 0.1) exhibited decent energy storage density (Jd = 0.58 J/cm3) and excellent thermal stability (the variation of Jd is less than 3% in the temperature range of 25-120 ℃), which could be a potential candidate for high energy density capacitors.