A high-tolerance BNT-based ceramic with excellent energy storage properties and fatigue/frequency/thermal stability

A novel perovskite lead-free solid solution of (Ba0.06Bi0.47Na0.47)(1-x)LaxTi1-y,ZryO3 were designed by dual-substitution of La3+ and Zr4+ for (Ba0.06Bi0.47Na0.47)(2+) and Ti4+. The frequency-, temperature- and fatigue-dependent energy storage properties of the materials were investigated. After the dopings of La3+ and Zr4+, the crystal structure of the ceramics remains unchanged; and tetragonal and rhombohedral phases coexist in all ceramics which exhibit a relaxor phase transition. The co-substitution of La3+ and Zr4+ leads to the high dielectric breakdown strength (DBS), large spontaneous polarization (P-s) and small remnant polarization (P-r) of the materials. The optimum energy storage properties are achieved at x/y = 0.02/0.04, giving high recoverable energy storage density of W-rec similar to 1.55 J/cm(3), excellent energy storage efficiency of eta similar to 72.6% and large dielectric breakdown strength of DBS similar to 136 kV/cm. Furthermore, the ceramic with x/y = 0.02/0.04 possesses superior durability of frequency (similar to 2-60 Hz), fatigue (similar to 10(3)) and temperature (similar to 25-245 degrees C).