Preparation and Dielectric Characterization of Lead‐Free Niobate Glass‐Ceramic Composites Added with Lu₂O₃

Abstract

Lead‐free niobate glass‐ceramic composites added with Lu2O3 were synthesized through melt‐quenching followed by controlled crystallization techniques. X‐ray diffraction and scanning electron microscopy showed that a minor phase determined as LuNbO4 was formed as the Lu2O3 addition exceeded 1 mol% in the basic glass‐ceramic. The formation of LuNbO4 was due to the saturation of Lu3+ doping in the major crystalline phases. Analyses of the dielectric properties and breakdown strength (BDS) indicated that they were closely related to the formation of this new minor phase. Although the dielectric constant was not increased continuously, the dielectric loss tangent was well controlled below 0.017, and the BDS increased from 40.2 to 47.2 kV/mm for the glass‐ceramic composites with increasing Lu2O3 addition. This study provided the Lu2O3 added lead‐free niobate glass‐ceramic as an attractive candidate for making high‐energy density capacitors.