Preparation and characterization of flexible, free‐standing, and easy‐fabricating BaTiO₃‐P(VDF‐CTFE) dielectric nanocomposite

Abstract

The flexible and free‐standing nanocomposite films were fabricated by a simple solution‐casting process using BaTiO3 nanoparticles as fillers and P(VDF‐CTFE) 91/9 mol% as polymer matrix. To obtain good wettability between ceramic and polymer, the coupling agent 3‐Aminopropyltriethoxysilane was used to modify the surface of BaTiO3 fillers. A good compatibility of BaTiO3 and P(VDF‐CTFE) was achieved when a small amount of coupling agent was used for the surface modification of BaTiO3 fillers; therefore, the nanocomposites with a dense and uniform microstructure was obtained. It was experimentally found that both dielectric constant and breakdown strength were increased with a suitable amount of coupling agent due to the good compatibility. A dielectric constant of 51 at 1 kHz was obtained with 30 vol% fillers and 2 wt% coupling agent, which was about four times of that for the pure P(VDF‐CTFE) film. When an appropriate amount of coupling agent was coated on fillers, the energy storage density of the composite system was improved. A maximal discharge energy‐storage density of 3.8 J/cm3 was obtained for the nanocomposite film with 5 vol% of BaTiO3 and 2 wt% coupling agent, which is much higher than that of the composites without coupling agent.

Modulation in polymer properties in PVDF/BCZT composites with ceramic content and their energy density capabilities

“…Finally, the dried film on the glass substrate has been peeled off and used for further analysis and testing as it is. [7,32,35] The thickness of pure PVDF and PVDF/BCZT composite films were measured and found to in the range 0.1 to 0.3 mm.…”

Enhanced direct‐current breakdown strength of Al2O3/epoxy resin composites through plasma fluoridation of fillers interface

“…The space charge inside the material was redistributed under DC electric field, leading to the local field distortion, which was harmful to the bulk insulation strength. [33][34][35] The space charge characteristics [36][37][38] of the samples were tested by the PEA method. During the test, the sample was polarized with a DC 10 kV/mm of electric field for 20 min.…”

Pluronic F127‐modified BaTiO3 for ceramic/polymer nanocomposite dielectric capacitor with enhanced energy storage performance

“…To further demonstrate the validity of F127 modification in improving the energy storage performance of BT-polymer nanocomposites, we compare the U d and η of BT@F127/P(VDF-HFP) in this work and other works as shown in Figure 12. Similar strategy to modify the surface of BT particles with organic surfactants such as F I G U R E 1 1 Charge-discharge efficiency of (A) BT@F127/P(VDF-HFP) and (B) BT/P(VDF-HFP) nanocomposites PVP, [33] KH-550, [35] PDA, [39] paraffin [52] or constructing a core-shell structure with a low-permittivity buffer like TiO 2 , SiO 2 have been considered to be efficacious. In contrast, the use of F127 herein as an organic surfactant is totally qualified to achieve better energy storage performance.…”

“…[32][33][34] Surfactant modification involves the simple operation and low cost, and plays an important role in improving the interfacial compatibility in organic/inorganic nanocomposite dielectrics. Yang et al [35] used 3-aminopropyl triethoxysilane as a coupling agent to perform the surface modification of BT particles which then demonstrated uniform dispersion in P(VDF-CTFE). The dielectric constant and breakdown strength were thus enhanced due to the reduction of interfacial defects.…”