Effect of Temperature on Dielectric and Impedance Characteristics of Graphene Oxide Thin Films

Graphene oxide (GO) thin films have attracted significant attention due to their unique combination of polar oxygen functional groups and a partially restored sp² carbon network, which makes their electrical behavior highly dependent on temperature and frequency. Unlike pristine graphene, GO exhibits a hetero-geneous structure in which localized charge carriers, structural defects, and interfacial effects strongly in-fluence its dielectric and impedance characteristics. These features make GO thin films promising for appli-cations in sensors, flexible electronics, energy storage devices, and resistive switching systems, where tem-perature-dependent electrical properties play a crucial role. This paper presents a practical framework for understanding temperature-tuned dielectric spectroscopy and impedance behavior of GO thin films deposit-ed on insulating substrates. By analyzing complex permittivity, electric modulus, and equivalent circuit models, we relate the observed frequency dispersion of dielectric constant (ε′) and dielectric loss (ε″) to mi-croscopic mechanisms such as Maxwell-Wagner interfacial polarization, charge hopping, and thermally acti-vated transport. With increasing temperature, relaxation processes become faster, shifting dielectric loss peaks to higher frequencies and reducing overall resistance. Nyquist plots exhibit shrinking semicircles at elevated temperatures, indicating enhanced charge mobility and partial reduction of GO. The DC conductiv-ity follows Arrhenius-type behavior, confirming thermally activated conduction.