High-Transmittance (K0.5Na0.5)NbO3 Ferroelectric Ceramics Modified by Sr(Bi0.5Ta0.5)O3

(1−x)(K0.5Na0.5)NbO3-xSr(Bi0.5Ta0.5)O3 (KNN-xSBT, x = 0.018, 0.02, 0.022, 0.024, 0.026, 0.028) transparent ferroelectric ceramics were prepared using the solid-phase method. The phase structure, microstructure, light transmittance, and optical and electrical properties of KNN-xSBT were investigated. It was found that the pseudo-cubic phase structure, higher compactness, and smaller grains of KNN can be effectively regulated by introducing the second component, SBT, thus achieving strong light transmittance and good energy storage performance for KNN-xSBT ceramics. When x = 0.022, the near-infrared band (1100 nm) transmittance of the ceramics reaches 72.2%, with energy storage density (Wrec) of 0.53 J/cm3; the maximum dielectric constant is obtained for ceramics at x = 0.018, with a value of 2935. The KNN-xSBT ceramic sample has relaxor ferroelectric properties and is an environmentally friendly lead-free transparent ferroelectric ceramic.