(K_0.5Bi_0.5)(Mg_1/3Nb_2/3)O₃‐modified Sr_0.7Bi_0.2TiO₃ lead‐free ceramics for energy storage applications

Abstract

In the present study, Sr0.7Bi0.2TiO3 is mixed with [(K0.5Bi0.5)(Mg1/3Nb2/3)O3] to form a solid solution of [(1 − x)SBT–x(KB)(MNb), x = 0.02, 0.04, 0.06, 0.1]. From the XRD results, it is indicated that KB is the main substituent for SBT ceramic at the A‐site. The breakdown strength (BDS) of ceramic gradually increases with an increase in doping content and achieves a high value of 280 kV/cm for x = 0.06. In addition, the 0.94SBT–0.06(KB)(MNb) ceramic shows excellent temperature stability (−55 to 140°C), a high recoverable energy density (Wd)—2.6 J/cm3, and an efficiency (η)—88% at 280 kV/cm. Therefore, 0.94SBT–0.06(KB)(MNb) ceramic is one of the possible materials for energy storage capacitor applications.