Enhanced optical transmittance and energy‐storage performance in NaNbO₃‐modified Bi_0.5Na_0.5TiO₃ ceramics

Abstract 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.