Influence of current collector electrode on the capacitive performance of electrodeposited PANI: insight gained from frequency and time domain analysis

Abstract

This article focuses on the choice and effect of current collector electrode on the performance-indicating parameters of supercapacitors. The electrochemical properties of polyaniline (PANI) deposited on platinized fluorine doped glass (Pt) and fluorine doped glass (F : SnO₂) current collectors are evaluated in depth by galvanostatic charge/discharge (GCD), cyclic voltammetry (CV) and impedance spectroscopy (IS). The GCD results show that the Pt-based electrode has better supercapacitive behavior than the F : SnO₂ electrode. Scanning electron microscopy (SEM) results reveal that a porous granular array of PANI is induced on the Pt electrode, whereas a compact granular morphology is induced on the F : SnO₂ electrode. Results from the CV are used to describe the dynamic variation of capacitance as a function of the applied bias. CV results reveal a higher value of capacitance for the Pt-based supercapacitor, which confirms the higher pore filling by electrolyte ions. Impedance measurements lead to determination of parameters such as equivalent series resistance, rate capability of electrodes and AC conductivity of supercapacitors. The results obtained here could aid understanding of how simple time and frequency domain experiments can be strategically used for quantitative characterization of supercapacitors.