High dielectric constant polymer nanocomposite for embedded capacitor applications

Abstract

The advancement in communication technology has led to the enormous attention to the development of energy storage materials. Polymer based materials are emerging as one of the potential components for high energy storage devices. Here, we report the development of flexible high-performance composites based on poly(vinyl alcohol) (PVA) and polyaniline (PANI) modified carbon nanofibers (CNF) by solution casting method. High dielectric constant, metal-insulator-metal (MIM) capacitor was fabricated using PANI/CNF/PVA composite film. At 100 Hz, thin film capacitor exhibited the highest capacitance of about 89.9 mF with a dissipation factor of 38.7. Excellent charge storage was observed at lower frequency range with moderate dissipation factor. Embedded capacitor prototype using PANI/CNF/PVA composite achieved a capacitance density of about 89.9 mF/cm2. Circuit application of the fabricated capacitor was also evaluated by measuring the charging and discharging times. The capacitor displays good reproducibility with a minor baseline shift. The incorporation of PANI/CNF into the PVA matrix enhanced the electrical and mechanical properties. The composite offered a high dielectric constant with lower dielectric loss and high charge density. The remarkable improvement in the dielectric properties originates from the interfacial polarization between the conducting PANI coated CNF and PVA matrix. This embedded capacitor technique improved the performance and reduced the cost of fabrication of traditional discrete capacitor technology.