Excellent thermal-stability and low dielectric loss of BaTiO3-Bi(Sr2/3Nb1/3) O3 solid solution ceramics in a broad temperature range applied in X8R

(1 - x)BaTiO3-xBi(Sr2/3Nb1/3)O-3 [(1 -x)BT-xBSN, 0.02 <= x <= 0.1] ceramics were synthesized by a traditional solid state reaction technique. The transition from tetragonal phase to pseudo cubic phase at 0.02 <= x <= 0.04 was observed in Raman spectra and X-ray diffraction patterns. As the BSN contents increased, the grain size increased. With adding Bi(Sr2/3Nb1/3)O-3, the thermal stability of permittivity and dielectric loss of ceramics got a good optimization. Especially, 0.9BT-0.1BSN ceramics have small Delta epsilon/epsilon(25 degrees C) values (<= +/- 15%) in a wide temperature range of -75 degrees C to 153 degrees C, high relative permittivity (-1505 to 1700) and low dielectric loss (tan delta <= 0.02) from - 88 degrees C to 200 degrees C, showing that BT-BSN ceramics are suitable for using in MLCCs of X8R. Impedance spectroscopy was analyzed the conduction and relaxation processes. The results showed that the relaxation and the conduction process in the high temperature region are thermally activated, and the oxygen vacancies are charge carriers.