Understanding the electrochemistry of polyaniline structural processes, charge, energy and reactive sensing capabilities through coulovoltammetry

Abstract

A detailed insight into the structural electrochemistry of polyaniline (PANI) has been presented through assessing the electrochemical redox processes of PANI by quantifying charge and electrical energy consumed during the reaction using coulovoltammograms. Coulovoltammetric responses during potential cycles are employed here as an efficient electrochemical tool to identify and separate the different structural components of the electrode reaction: oxidation/diffusion (fast), oxidation/relaxation (slow), reduction/diffusion (fast) and reduction/compaction (slow). The reversible and irreversible oxidations and reductions with respect to anodic and cathodic potential limits have been identified and quantified in terms of consumed charge. The accurate potential window of the PANI electrode that only has reversible oxidation/reduction is identified from the coulovoltammogram. Further, the sensing characteristics of PANI reaction have been studied using coulovoltammetry and proved that the electrochemical reactions of polyaniline can sense their working ambient such as electrical, chemical and thermal working conditions without additional connectivities through consumed charge and/or electrical energy consumed during the reaction as sensing parameters. This investigation offers valuable insight into PANI’s versatile applications as a sensing biomimetic device.