Effect of Different Al/Si Ratios on the Structure and Energy Storage Properties of Strontium Barium Niobate-Based Glass-Ceramics

Strontium barium niobate-based glass-ceramics (BSN-AS) with various Al/Si ratios have been prepared through melt casting followed by controlled crystallization. The effect of the various Al/Si ratios on the phase evolution, microstructure, dielectric properties, and energy storage density, and the relationship between the breakdown strength properties and the activation energy E a of BSN-AS glass-ceramics, were investigated. The results reveal that the microstructure of BSN-AS glass-ceramics gradually becomes dense and uniform, and the phenomenon of reunited grains is effectively improved in a certain range of Al/Si ratios. With the Al/Si ratios increasing, the breakdown strength increases to a maximum value and then decreases drastically. For the relationship between breakdown strength properties and activation energy E a, it was found that the various trends between breakdown properties and activation energy E a of the BSN-AS glass-ceramics are opposite. In this study, the energy storage densities reach 4.8 J/cm3 by adjusting the Al/Si ratios in the BSN-AS glass-ceramics.