Simultaneously achieved high energy-storage density and efficiency in BaTiO_3-Bi(Ni_(2/3)Ta_(1/3))O_3 lead-free relaxor ferroelectrics

摘要

The development of Pb-free energy-storage materials with excellent stability has attracted attention in recent times due to the energy and environmental crises. In this study, a series of (1 - x)BaTiO_3-xBi(Ni_(2/3)Ta_(1/3))O_3 [(1 - x)BT-xBNT, x = 0.08, 0.1, 0.12, 0.14, and 0.16] relaxor ferroelectric ceramics was designed and synthesized. A highly recoverable energy-storage density (W_(rec)) of 2.63 J/cm~3 and energy-storage efficiency (η) of 90% are obtained simultaneously in 0.84BT-0.16BNT ceramics. This excellent energy-storage characteristic may be attributed to the enhanced relaxor characteristic and its dense microstructure. In addition, excellent stability of energy-storage properties (variation in the W_(rec) ＜ 4% over 20-100 °C, W_(rec) ＜ 13.1% over 1 to 200 Hz and W_(rec) ＜ 3% after 10~4 cycles) can also be observed. These results indicate that the 0.84BT-0.16BNT ceramics can be considered as potential Pb-free candidate materials for applications in advanced energy-storage applications.