FREQUENCY DEPENDENT DIELECTRIC PROPERTIES OF BT/PARYLENE NANOCOMPOSITES FOR ENERGY STORAGE APPLICATIONS

摘要

With climbing worldwide oil prices and global warming, energy crisis poses a threat to living standards, economy, and even global environment. Nanodielectrics become one of the new materials activated to play a unique role in sustainable and clean energy production, energy transportation, energy storage, and end usage. Based on our recent research on frequency-dependent dielectric properties of BaTiO_3 (BT) single domain, BT/parylene nanodielectric composites have been examined in wide-ranging frequency at room temperature by several theoretical models. The projected models combined with Debye type of dissipation and soft mode theory to obtain more precise frequency dependent dielectric spectrum. Among the others, Wiener mixture rule, Lichtnecker model, Rayleigh model, Yamada rule, Maxwell-Wagner model, modified Kerner model were used to find frequency dependent nanocomposites dielectric spectrum. The predicted results are compared with our experimental results and explored the frequency dependent dielectric behavior of nanodielectric composites. The dielectric constant decreases while dielectric loss increases with increasing frequency due to at very high frequency, only electronic polarization can occur. This investigation provides the fundamental knowledge on dielectric properties of nanocomposites with a wide frequency range instead of trial-and-error strategy of experiments for the future development of energy storage devices.