Cole-Cole Modelling of Reduced Graphene Oxide Decorated CuO Nano-Spheres Based Waterproof Conductive Ink for Flexible Electrodes

Flexible electrodes are developed using a novel conductive ink with various ratios of graphene nanoflakes decorated with copper nanospheres as a conductive filler. These electrodes represent potential candidates for energy storage devices and solid-state batteries. The electrodes are studied by AC measurements in the range of (0.1 Hz-500 kHz). Electrical impedance measurement data have been utilized for modeling the electrical properties of the conductive ink. The fitting is done using Z-Fit software and a randomized method followed by the Levenberg-Marquardt using the Cole-Cole model. The equivalent circuits are simulated by the Z-Sim software and values are compared with the theoretical values. The error between simulation value and theoretical value was found to be minimum. The aim of the work described in the present paper is to establish an equivalent electrical circuit for the conductive ink electrodes. The best and simplest circuit representation which gives the best fitting for the Cole-Cole and Nyquist plots consists of two resistors in parallel with a capacitor in series. The values of the electrical components are tabled, and the Cole-Cole plot is fitted to the measured data.