Crystallization kinetics behaviour and dielectric properties of strontium barium niobate-based glass–ceramics

Strontium barium niobate-based glass–ceramics (SBN–glass–ceramics) with various B2O3/SiO2 ratios have been prepared by powder-melting method followed by controlled crystallization. The effects of different B2O3/SiO2 ratios on the phase evolution, microstructure, dielectric property, breakdown strength and energy storage density of the SBN–glass–ceramics were studied. In addition, the crystallization kinetics behavior of the SBN–glass was analyzed by differential scanning calorimeter method. The microstructure of the SBN–glass–ceramics by replacing SiO2 with B2O3 becomes dense and uniform dramatically. Through the analysis of the crystallization kinetics, replacing a small amount of SiO2 with B2O3 can make the SBN–glass less stable, which is conducive to crystallization in the SBN–glass. When the ratio of B2O3/SiO2 is 1.5/33.5 in the SBN–glass–ceramics, the dielectric constant is up to 143.2 and the optimized theoretical energy storage density of 7.4 J/cm3 is achieved at room temperature, which is about 2 times higher than that of the boron-free SBN–glass–ceramics.