Crystallization behavior and dielectric properties of K2O–SrO–Nb2O5–B2O3–Al2O3–SiO2 glass-ceramic for energy storage

Abstract A new K 2 O–SrO–Nb 2 O 5 –B 2 O 3 –Al 2 O 3 –SiO 2 (KSN-BAS) glass-ceramic system has been prepared by conventional controlled-crystallization method. The crystallization behavior and dielectric properties of the glass-ceramics were investigated. The X-ray diffraction analysis showed that the KSr 2 Nb 5 O 15 and SrNb 2 O 6 phases with tungsten bronze structure were precipitated from the glass matrix, as the crystallization temperature increased, the AlNbO 4 phase was observed. The microstructure observed the sizes of grains became larger and presented the grain reunion severely. The dielectric constants of all the samples exhibited excellent stability from −90 °C to 120 °C and low dielectric losses less than 0.03. A maximum dielectric constant was obtained at annealing of 900 °C. The dielectric breakdown strength (BDS) reduced as the crystallization temperature increased. A maximum BDS can attain1213.76 kV/cm and a maximum energy storage density can reach up to 4.41 J/cm 3 .