Evaluation of Supercapacitive Properties of a PPY/PANI Bilayer Electrodeposited onto Carbon-Graphite Electrodes Obtained from Spent Batteries

Recently, many efforts have been made to reuse spent batteries in response to the growing demand for sustainable materials production. In parallel, supercapacitors have attracted significant attention for their use in addressing some of the limitations of conventional capacitors and batteries. In this context, this paper describes the preparation, characterization, and supercapacitive performance evaluation of carbon-graphite (CG) electrodes obtained from spent zinc-carbon batteries and modified with polypyrrole (PPY) and polyaniline (PANI). The parameters of PPY and PANI electropolymerization were optimized. CG/PPY, CG/PANI, and CG/PPY/PANI electrodes were obtained to compare their electrochemical responses. Cyclic voltammetry (CV), galvanostatic charge-discharge curves (GCDC), and electrochemical impedance spectroscopy (EIS) were used to evaluate the pseudocapacitive properties of the CG/PPY/PANI-modified electrode. The CG/PPY/PANI electrode showed a specific capacitance of 3416 mF cm-2 in a current density of 2 mA cm-2 and a retention capacity of 76% after 850 GCDC cycles. Thus, CG/PPY/PANI electrodes are shown to be good candidates for use in the development of energy storage devices. In addition, reused CG electrodes from spent batteries have other advantages like low cost, facile construction, and environmental friendliness.