Dielectric Properties of PEO/MC/Graphene Oxide Nanocomposite Films: Experiment, Modeling, and MATLAB Simulation

This work investigates the broadband dielectric response of solution-cast poly (ethylene oxide)/methyl cellulose blend films reinforced with graphene oxide (0–20 wt %). The real and imaginary parts of the permittivity were obtained from capacitance-derived dielectric spectra measured over 12 Hz–30 kHz, and were used to calculate the loss tangent and the alternating-current conductivity. All compositions show a strong low-frequency dispersion attributed to interfacial polarization, with the real permittivity decreasing monotonically with frequency. The alternating-current conductivity follows a universal power-law dependence on frequency, and the extracted exponents indicate a transition from broader, slower dynamics in the neat polymer blend to more dispersive transport after adding graphene oxide. Notably, films with 10–20 wt % graphene oxide exhibit reduced dielectric losses around 1 kHz while maintaining moderate permittivity, defining a practical operating window for energy-conditioning dielectrics. Non-Debye relaxation behavior was quantified using Cole–Cole and Havriliak–Negami functions, and parameter-driven simulations implemented in MATLAB were consistent with the measured spectra. Overall, the results provide composition–property guidance for tuning permittivity and losses in water-processed polymer–graphene oxide dielectrics for capacitors and sensors.