Development of Binary Pd@PPyC-Bi2O3 Nanocomposite Sensor for Trace-Level Detection of 2,4-Dinitrophenol in Wastewater via Linear Sweep Voltammetry

Abstract

Here, an electrochemical sensor has been developed for the efficient determination of 2,4-dinitrophenol (2,4-DNP) in aqueous medium at neutral pH (7.0) phase. The chemical sensing probe was developed by modifying a flat glassy carbon electrode (GCE) with palladium-doped polypyrrole carbon–bismuth oxide nanocomposites (Pd@PPyC-Bi₂O₃ NCs), synthesized via a hydrothermal route. The electrochemical performance of the NCs fabricated with PEDOT:PSS conducting polymers modified electrode (Pd@PPyC-Bi₂O₃ NCs/PEDOT:PSS/GCE) was evaluated by using linear sweep voltammetry (LSV), which revealed a wide linear detection range (LDR) of 10.0 – 90.0 µM for 2,4-DNP. The calibration plot exhibited excellent linearity, with the sensor demonstrating a high sensitivity of 109.70 µA.µM⁻¹.cm⁻². The limit of detection (LOD) was obtained to be 0.92 ± 0.05 µM. In addition, the sensor exhibited good repeatability and stability under repeated measurements. Its practical applicability was further validated by successfully detecting 2,4-DNP in environmental collected waste water samples from different sources, with satisfactory recovery results. Overall, this study introduces a sensor Pd@PPyC-Bi₂O₃ NCs/PEDOT:PSS/GCE probe as a good electrochemical platform for efficient monitoring of 2,4-DNP by LSV, offering significant potential for environmental analysis and pollution control in a broad scales.