Enhanced energy storage properties of barium strontium titanate ceramics prepared by sol-gel method and spark plasma sintering

Dense Ba0.4Sr0.6TiO3ceramics with fine grains and uniform microstructure were prepared by sol-gel method and spark plasma sintering (SPS). The dielectric properties, microstructures, and energy storage performance of spark plasma sintered Ba0.4Sr0.6TiO3 ceramics were evaluated. Fine Ba0.4Sr0.6TiO3 powders were synthesized by sol-gel method at above 750 °C. SPS technique showed its advantages in suppressing exaggerated grain growth and increasing the relative density of Ba0.4Sr0.6TiO3ceramics. Diffuse phase transition and nearly linear P-E behavior were observed in all samples. Moderate dielectric constant (∼960), low dielectric loss (∼0.003), high electrical breakdown strength (∼240 kV/cm), significantly enhanced energy storage density (∼1.23 J/cm3) and ultrahigh energy storage efficiency (∼94.52%) were obtained in Ba0.4Sr0.6TiO3 ceramics by using sol-gel method and spark plasma sintering.