Environmental applications of an ultrasonically synthesized and PEG assisted Yb2O3/ZnFe2O4 nanocomposite for dye and herbicide degradation and electrochemical sensing of catechol

Abstract

This study effectively generated zinc ferrite (ZnFe₂O₄) and ytterbium oxide (Yb₂O₃) nanoparticles (NPs) using the co-precipitation method. Using the synthesized NPs, a binary nanocomposite Yb₂O₃/ZnFe₂O₄@PEG supported by polyethene glycol (PEG) was formed via ultrasonication. The morphological, structural, functional, and optical features of the produced NPs and the binary nanocomposite were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and UV-visible spectroscopy. The photocatalytic activity of the NPs and the nanocomposite against the pesticide glyphosate and the Brilliant Blue FCF dye was investigated under the influence of visible light. In contrast to the individual NPs, the Yb₂O₃/ZnFe₂O₄@PEG nanocomposite had noticeably better photocatalytic activity. It achieved 86% and 91% degradation of the dye and pesticide, respectively, under 90 minutes, which may be explained on the basis of enhanced charge separation, synergistic interactions, and increased surface activity. Moreover, the Yb₂O₃/ZnFe₂O₄@PEG nanocomposite was tested for catechol sensing through the electrochemical method. The cyclic voltammetry analysis showed that the bare GCE produced a negligible current response, whereas the nanocomposite-modified electrode displayed pronounced redox peaks in the presence of catechol, confirming its strong electrocatalytic activity. The sensor exhibited a linear response for catechol in the concentration range of 40–100 µM, with a sensitivity of 0.367 µA µM⁻¹ cm⁻² and a limit of detection of 11.52 µM, confirming its suitability for sensitive electrochemical monitoring. The resulting binary nanocomposite can be used as a photocatalyst to effectively break down hazardous dyes and pesticides, hence enabling environmental cleanup applications.