Porous Barium Strontium Titanate Preparation And Application In Composite Material

In this paper, the Nano-powder of BaxSr1-xTiO3 (x=0.2、0.3、0.5 and 0.6) with different mole ratio of barium strontium was synthesized by direct-reactive precipitation process. BaxSr1-xTiO3/PVDF nanocomposites are fabricated by physical blending. And then test performance of composites to make sure the composition of BaxSr1-xTiO3 was Ba0.6Sr0.4Ti03 with 50 nm. The homogeneous porous Ba0.6Sr0.4TiO3 nano-powder was prepared through the sol-gel method. The influence of experimental conditions such as coated layer、P123 dose and reaction temperature were studied. Added the porous Ba0.6Sr0.4TiO3 to PVDF to composite Bao.6 Sr0.4TiO3/PVDF composites, and the electrical properties of Bao.6Sr0.4Ti03/PVDF composites were evaluated.The direct-reactive precipitation process can synthesis the cubic phase, spherical and size about 50 nm BaxSr1-xTiO3 (x=0.2、0.3、0.5 and 0.6) nano-particle. At 1 kHz, the dielectric constant of the composite are around 14, with 7 vol% powder adding proportion, and the breakdown strength of Ba0.6Sr0.4TiO3/PVDF composites was 219.24 kV·mm-1, the maximal energy storage density of 2.91 J·cm-3 was obtained in the Ba0.6Sr0.4TiO3/PVDF composites according to the D-E loops, which was about 1.68 times compared with pure PVDF.At operating conditions such as 65℃, with 0.1 ratio of P123 and cladding layer and solid powder coating in a proportion of 2:1, homogeneous porous Ba0.6Sr0.4TiO3 nano-particles can be synthesized by sol-gel process. The dielectric constant of the porous Ba0.6Sr0.4Ti03/PVDF composites was 15 with 7 vol% proportion of porous powder, at 1 kHz. And the breakdown strength of the composite was 289.64 kV·mm-1, depending on the composites dielectric hysteresis loop, the maximal energy storage density of 3.70 J·cm-3 was obtained in the Ba0.6Sr0.4TiO3/PVDF composites with 7 vol% porous Ba0.6Sr0.4TiO3 nano-particles, which was 2.14 times than the energy storage density of pure PVDF; As improved the porous powder adding ratio in composites, the dielectric constant of the composite was improved, but the breakdown strength and the energy storage density were dropped. The specific surface area of composites was increased by the addition of porous Ba0.6Sr0.4TiO3, leading to the composites can capture more electronic to increase the breakdown strength. Besides, the remained polarization of composites can be reduced by the addition of paraelectric porous Ba0.6Sr0.4TiO3 nano-particles, and the energy storage density was enhanced.