The influences of B-site doping on ferroelectric and energy-storage properties of Bi0.5(Na0.82K0.18)0.5TiO3-LiSbO3 ceramics

Single-phase Bi-0.5(Na0.82K0.18)(0.5)Ti1-xMxO3-0.01LiSbO(3) (BNKT-LS-xM) (M = Ta, Nb or Zr, 0 <= x <= 0.05) lead-free ceramics are prepared by a solid-state reaction method. The influences of Ta5+, Zr(4+)or Nb5+ doping at B-site of perovskite structures on the crystal structure, chemical structure, ferroelectric and energy-storage properties of BNKT-LS ceramics are systematically investigated. Although the introduction of Ta5+, Zr4+ and Nb5+ at B-site could disturb the long-range ferroelectric ordering, Ta5+ or Nb5+ doping results in excellent thermal stability of the energy-storage density (as large as 0.7 J cm(-3)) at elevated temperatures (50 degrees C-200 degrees C) with a high energy-storage efficiency (>90%). The results demonstrate that the lead-free BNKT-LS-xM ceramics are promising dielectric materials that can be finely tuned for electrical energy storage with high energy storage efficiency and a wide range of operating temperature.

Automated summary

By doping with Ta5+ or Nb5+ in BNKT-LS ceramics, a lead-free ceramic material with good thermal stability and high energy storage efficiency can be obtained.