Improved energy storage performances of lead-free BiFeO 3 -based ceramics via doping Sr 0.7 La 0.2 TiO 3

Substantial attention for dielectric ceramic capacitors toward lead-free has been driven by the enhanced awareness of environmental protection. However, the unsatisfying breakdown strength ( E b ) and comparatively low efficiency ( η ) becomes an obstacle for their widespread application. Here, environment-friendly lead-free relaxor ferroelectric (1-x) (0.67BiFeO 3 -0.33Ba 0.8 Sr 0.2 TiO 3 ) -xSr 0.7 La 0.2 TiO 3 + 0.1 wt% MnO 2 (BFO-BST-SLT) ceramic is reported as an efficient route to possess excellent E b and high η simultaneously. The doping of SLT can significantly suppress the grain growth, improve the relaxation behavior, and thus increasing the E b and η of the ceramics. Consequently, the corresponding ceramics with x = 0.3 achieves good discharged energy density of ~2.55 J/cm 3 and ultrahigh η of ~92%. Notably, it presents outstanding charging/discharging performances with fast charging/discharging time (~0.0266 μs), power density (~28.11 MW/cm 3 ) along with current density (~468.5 A/cm 2 ). Together with great temperature stability, frequency stability and cycle stability, this contributes provides a crucial way to prepare lead-free dielectrics for next-generation pulsed power capacitor applications.