A high-tolerance BNT-based ceramic with excellent energy storage properties and fatigue/frequency/thermal stability. Issue 17 (1st December 2019) - Wang, Hua
Abstract: A novel perovskite lead-free solid solution of (Ba0.06 Bi0.47 Na0.47 )1- x La x Ti1- y Zr y O3 were designed by dual-substitution of La 3+ and Zr 4+ for (Ba0.06 Bi0.47 Na0.47 ) 2+ and Ti 4+ . The frequency-, temperature- and fatigue-dependent energy storage properties of the materials were investigated. After the dopings of La 3+ and Zr 4+, 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 La 3+ and Zr 4+ 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 ~1.55 J/cm 3, excellent energy storage efficiency of ƞ ~72.6% and large dielectric breakdown strength of DBS ~136 kV/cm. Furthermore, the ceramic with x / y = 0.02/0.04 possesses superior durability of frequency (~2–60 Hz), fatigue (~ 10 3 ) and temperature (~ 25–245 °C).