2-Dimensional Magnesium Oxide/Polyaniline Nanocomposite Modified Glassy Carbon Electrode for Electrochemical Detection of Dopamine and 4-Nitrophenol

In this study, we have developed an electrochemical sensor based on a polyaniline (PANI) integrated magnesium oxide nanosheet (MgO-NSs) modified glassy carbon electrode (GCE) for the rapid electrochemical detection of dopamine (DA) and 4-nitrophenol (4-NP). 2-D MgO-NSs were synthesized using a straightforward one-step sugar-blowing method, and PANI was synthesized by the oxidative polymerization of aniline. The nanocomposite (PANI-MgO) was prepared by simple mechanical blending of MgO-NSs with PANI. The as-synthesized nanocomposites were characterized using several analytical techniques to determine their morphological and microstructural properties. The as-synthesized PANI, MgO, and PANI-MgO were further electrochemically characterized using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) techniques. The fabricated PANI-MgO/GCE showed a considerable increase in the redox peak currents of DA and 4-NP, suggesting that PANI-MgO/GCE substantially enhances the electrocatalytic oxidation of DA and the reduction of 4-NP. The analytical performance of PANI-MgO/GCE for the detection of DA and 4-NP was investigated using Differential Pulse Voltammetry (DPV). The developed sensor was successfully applied for the detection of DA and 4-NP in real samples with good recovery results. This work reports the successful synthesis of a nanocomposite consisting of 2-D MgO nanosheets and Polyaniline (PANI-MgO). The PANI-MgO-modified Glassy Carbon Electrode provides higher electroactive sites and improved conductivity. The fabricated sensor is utilized for the selective electrochemical sensing of the neurotransmitter Dopamine and the water pollutant 4-Nitrophenol, demonstrating a low limit of detection.+ image