Dielectric study and Cole–Cole plots of poly(methyl methacrylate) doped with nanostructured metal oxides

This paper presents an analysis of the dielectric properties (dielectric constant, dielectric loss, AC conductivity, dielectric modulus, and Cole–Cole plots) of PMMA/ Metal oxide nanocomposite films. 8% wt% metal oxide = CuO, ZnO and NiO nanoparticles (NPs) with a particle size 19, 30 and 10 nm respectively were used. FT-IR, X-ray and HRSEM were used to differentiate PMMA/Metal oxide nanocomposite films prepared using solution casting technique. The electrical characteristics' performance was investigated across a wide frequency range (10 Hz–20 MHz). The dielectric constant of the films increases with increasing temperature and decreases with increasing frequency. The presence of resonant peaks in the loss tangent is due to the dielectric relaxation processes in these nanocomposites. The temperature dependence of AC conductivity confirmed the Arrhenius law. The activation energy for all films would be between 0.2 and 0.40 eV, indicating that the transport processes were based on hopping phenomena. The universal dispersion relaxation (UDR) is used to explain the variation in AC conductivity as a function of frequency, and it is suggested that correlated barrier hopping (CBH) would be used to explain the AC conductivity. The dielectric characteristic was described using the electrical modulus formalism, indicating that charge carrier hopping is the most likely conduction mechanism. The average relaxation time has been calculated using temperature-dependent Cole–Cole plots.