Enhanced optical transmittance and energy-storage performance in NaNbO3-modified Bi0.5Na0.5TiO3 ceramics

Dielectric ceramics with both excellent energy storage and optical transmittance have attracted much attention in recent years. However, the transparent Pb-free energy-storage ceramics were rare reported. In this work, we prepared transparent relaxor ferroelectric ceramics (1 − x )Bi 0.5 Na 0.5 TiO 3 – x NaNbO 3 (BNT– x NN) by conventional solid-state reaction method. We find the NN-doping can enhance the polarization and breakdown strength of BNT by suppressing the grain growth and restrained the reduction of Ti 4+ to Ti 3+ . As a result, a high recoverable energy-storage density of 5.14 J/cm 3 and its energy efficiency of 79.65% are achieved in BNT–0.5NN ceramic at 286 kV/cm. Furthermore, NN-doping can promote the densification to improve the optical transmittance of BNT, rising from ∼26% ( x = 0.2) to ∼32% ( x = 0.5) in the visible light region. These characteristics demonstrate the potential application of BNT– x NN as transparent energy-storage dielectric ceramics.