Electrochemical sensor for catechol detection: Leveraging ITO@TiO₂/RGO/Pt nanocomposites for enhanced water quality monitoring

Recent advancements in sensor technology have led to the development of an ITO@TiO₂/RGO/Pt nanocomposite-based electrocatalyst for the detection of catechol (1,2-dihydroxybenzene) in water. Catechol is a harmful contaminant affecting human and aquatic life through polluted water and food. The nanocomposites were characterized using UV–Vis, FT-IR, FESEM, EDX, XRD, BET, zeta potential, and particle size analysis to evaluate their functionalities, morphology, composition, and surface properties. ITO glass was modified with these nanocomposites via the drop-casting method. Electrochemical characterization, including cyclic voltammetry and impedance spectroscopy, indicated optimal sensor performance with a scanning rate of 100 mV/s and pH 7 PBS, displaying a strong catechol response. The sensor demonstrated a linear range of 5–105 µM with limits of detection (LOD) and quantification (LOQ) of 0.013 and 0.046 µM, respectively, and recovery rates between 97.1 % and 101.3 % in water samples. It achieved over 7,580 turnovers with a TOF of 97.5 (mol Catalyst)^-1·(min)^-1, though the TOF decreased to 34.45 after multiple uses.