Synthesis and thermal stability, electrical conductivity and dielectric spectroscopic studies of poly (ethylene-co-vinyl alcohol)/graphene oxide nanocomposite

Abstract

A new nanocomposite was successfully synthesized by incorporating the prepared graphene oxide into poly(ethylene-co-vinyl alcohol) (EVOH) copolymer via simple solution casting method. XRD, FT-IR, SEM and TGA analysis were used to characterize the current nanocomposite. AC electrical transport properties of the nanocomposite were studied in the frequency range (10 Hz-1MHz) over the temperature range (298–423 K). The AC conductivity results were interpreted using jump relaxation model and were found to obey the universal double power law. The conduction mechanism inside the current samples has changed from non-overlapping small polaron tunneling to correlated barrier hopping. The calculated barrier height has indicated that the predominant charge carriers in the EVOH/GO nanocomposite are the single polarons and not bipolarons. The enhancement in σac of the EVOH-based nanocomposite, making these samples highly recommended for use in energy storage applications such as; electronic capacitors where materials with high dielectric constant and low dielectric loss are required.