Assessment of environmentally unsafe pollutants using facile wet-chemically prepared CeO2–ZrO2 nanocomposites by the electrochemical approach

Abstract

Here, a selective and sensitive 4-methoxyphenol (4-MP) chemical sensor was developed with a co-doped CeO₂–ZrO₂ nanocomposite (NC) modified glassy carbon electrode (GCE) as a sensor probe. The wet-chemical preparation method was implemented to synthesize the co-doped CeO₂–ZrO₂ NCs in a highly alkaline aqueous medium. The resulting NCs were finally characterized by using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDS) analysis to explore ionization states of the existing atoms, crystallinity, morphology, and elemental composition methodically. A current versus concentration of 4-MP plot known as calibration of the sensor is used to calculate the sensor analytical parameters such as the dynamic range of 4-MP detection (0.1 nM to 0.01 mM), sensitivity (10.8418 μA μM⁻¹ cm⁻²), and limit of detection (95.71 ± 4.79 pM). The designed 4-MP sensor exhibits good reproducibility, long-time stability, and high efficiency in measuring real environment-contaminated samples by using a CeO₂–ZrO₂ NC/GCE sensor probe. Therefore, an efficient method is proposed, which develops to protect the environmental ecosystem as well as the healthcare fields.