Revolutionizing electrochemical sensing: Ultra-sensitive non-enzymatic detection of 4-aminophenol with a novel cu-PANI nanocomposite

Abstract

This study presents an electrochemical sensor utilizing copper polyaniline (Cu-PANI) nanocomposites (NCs) for the detection of 4-aminophenol. Polyaniline (PANI) is synthesized through the in-situ chemical oxidation polymerization method, which involves the concurrent polymerization of aniline and the generation of copper nanoparticles within the polymer matrix. It is suggested that the copper nanoparticles interact with the mobile groups of polyaniline via electrostatic forces. Fourier transform infrared (FTIR) studies reveal that the synthesized nanocomposites contain functional groups and confirm the interaction between PANI and copper. The surface morphology of the Cu-PANI NCs is examined using scanning electron microscopy (SEM). The electrochemical performance of the Cu-PANI NCs toward 4-AP is assessed through voltammetry (CV) and differential pulse voltammetry (DPV). It is noted that the glassy carbon electrode (GCE) modified with Cu-PANI (Cu-PANI NCs@GCE) shows an outstanding CV response in the presence of a supporting electrolyte (0.1 M H₂SO₄) at 0.52 V. Differential pulse voltammetry (DPV) identifies 4-AP within the linear range of 1 to 2000 μM at Cu-PANI NCs@GCE. This sensor is distinguished by its low detection limit of 0.002 μM, high sensitivity of 15.462 μA mM¹ cm², exceptional selectivity in complex matrices, and cost-effectiveness, which make it superior to the previously reported sensor, making it ideal for environmental applications. The Cu-PANI NCs-based electrode material is relatively low-cost, robust, selective, sensitive, and possesses an excellent volume-to-surface ratio. The conclusion is that the electrochemical sensor demonstrates proficient sample-analyzing activity and is capable of effectively analyzing sewage, tap water, and industrial wastewater samples.