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

Abstract 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.