Lead-free high-temperature dielectrics with wide temperature stability range induced from BiFeO3-BaTiO3-based system

Lead-free BNSTNZ ((Bi,Na,Ba,Sr)(Ti,Nb,Zr)O-3)-modified BF35BT (0.65BiFeO(3)-0.35BaTiO(3)) dielectrics were investigated by conventional solid-state reaction method. Dielectric permittivity of BFBT-BNSTNZ ceramics was suppressed through addition of BNSTNZ content, while dielectric temperature stability range was expanded from 105 ?C to 412 ?C as BNSTNZ content increases from 0.025 to 0.1, due to the ferroelectric-relaxor phase transition. In particular, x = 0.10 exhibits the widest stability temperature range from 88 ?C to 500 ?C having small variation of (delta epsilon(m)/epsilon(m 150 ?C) <= 15%) with high dielectric permittivity (> 1000) and low dielectric loss (tan? <= 0.1) in temperature range from 50 ?C to 250 ?C. Moreover, high room temperature energy storage density (W-store) of 0.75 and 0.57 J/cm(3) with energy storage efficiency (?) of 57% and 78% for x = 0.03 and x = 0.10, respectively, was achieved. These results indicate that BFBT-BNSTNZ can be a promising system for high-temperature dielectric and energy storage applications.

Automated summary

By adding BNSTNZ modification, the dielectric permittivity of BFBT-BNSTNZ ceramics can be suppressed and the temperature stability range can be expanded. In particular, at x = 0.10, it has the widest stability temperature range and high dielectric permittivity with low dielectric loss.