Nanocomposites with BaTiO3-SrTiO3 hybrid fillers exhibiting enhanced dielectric behaviours and energy-storage densities

作者：Yu, Dan; Xu, Nuo-xin; Hu, Liang; Zhang, Qi-long^*; Yang, Hui

来源：Journal of Materials Chemistry C, 2015, 3(16): 4016-4022.

DOI：10.1039/c4tc02972k

• FERROELECTRIC POLYMER NANOCOMPOSITES
• METAL-OXIDE NANOCOMPOSITES
• POLY(VINYLIDENE FLUORIDE)
• HIGH-PERMITTIVITY
• BREAKDOWN STRENGTH
• ASPECT-RATIO
• COMPOSITES
• NANOPARTICLES
• NANOFIBERS
• CONSTANT

Herein, small loadings of SrTiO3 nanowires (ST NWs) were synthesized and grafted onto the surface of BaTiO3 nanoparticles (BT NPs) in a hydrothermal process. Nanocomposites comprised of P(VDF-HFP) matrix and ceramic fillers were prepared using BT-ST nanocrystals of different molar ratios. Microstructure and thermal analysis confirm that BT NPs have been successfully functionalized with polyphenol-Sr2+ shells on the surface, and the BT-ST-P(VDF-HFP) nanocomposites can obtain a higher thermal stability than both pure P(VDF-HFP) and BT-P(VDF-HFP) composites. Dielectric properties measured at various frequencies and temperatures indicate that the nanocomposites with several BT-ST ratios exhibit enhanced dielectric properties over a wide frequency range. With a BT-ST molar ratio of 2 and the dielectric constant of 7.5 vol% sample can increase by 3.2 and dielectric loss can decrease by 0.015, compared with BT-P(VDF-HFP) nanocomposites. In addition to the dielectric behaviours progress, the BT-ST-P(VDF-HFP) composites also possess higher electrical displacements and corresponding energy-storage densities compared to BT-P(VDF-HFP) nanocomposites. The energy density of the optimal BT-ST-P(VDF-HFP) sample is four times higher than that of pure P(VDF-HFP) under an electric field of 20 kV mm(-1). All the improved performances suggest an easy method to fabricate nanocomposites bearing potential electrical applications.

• 出版日期2015
• 单位浙江大学