High energy storage performance of Na(Nb0·95Ta0.05)O3/ Na0·5Bi0·5TiO3 lead-free ferroelectric ceramics

NaNbO 3 -based lead-free ferroelectric ceramics are considered to be one of the most promising energy storage materials. In this paper, The (1- x )Na(Nb 0 · 95 Ta 0.05 )O 3 - x (Bi 0 · 5 Na 0.5 )TiO 3 ceramics have been investigated in detail. The SEM images presented that the addition of BNT obviously improved the bulk densities which reached a maximum at x = 0.4, corresponding to a high breakdown field strength of 240 kV/cm. The XRD patterns showed that the strongest diffraction peak was observed in the case of x = 0.4 and 2 θ = 33.2°, implying that the two phases formed a superior mutual solubility, because of which a significant polarization intensity of 38.2 μC/cm 2 was obtained. As a result, the 0.6NaNbO 3 -0.4(Bi 0 · 5 Na 0.5 )TiO 3 ceramics exhibited an excellent discharge energy density of 3.607 J/cm 3 , while the energy storage efficiency was calculated to be 72%.