Graphene-oxide supported HgO/Y₂O₃ nanocomposite for electrochemical detection of thiourea

In the present approach it was shown that for the detection of Thiourea (TU; CH₄N₂S) using binary Mercury oxide and Yttrium oxide (HgO/Y₂O₃) nanostructure materials in combination with Graphene oxide (HgO/Y₂O₃-GO) act as an advanced nanocomposites electrochemical sensor probe. Direct solid state chemical methods were used for preparing Hg/Y₂O₃-GO nanocomposites (NCs) and then characterized by using several techniques. The techniques were utilized for the analysis of the crystallinity, band-gap energy, surface morphology, surface area, and the functional characteristics of the synthesized HgO/Y₂O₃-GO NCs such as powder X-ray diffraction (XRD), UV/visible spectroscopy (UV), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Brunauer-Emmett-Teller analysis (BET), and Fourier transform infrared spectroscopy (FT-IR). Finally, the suggested sensor was tested for its performance, using linear sweep voltammetry (LSV) and cyclic voltammetry (CV). Subsequently, an electrochemical sensor analyzing performance and analysis in phosphate buffer solution (PBS) is evaluated using the synthesized HgO/Y₂O₃-GO NCs and the glassy carbon electrode (GCE) was developed by adding 5 % Nafion. The proposed sensor probe (HgO/Y₂O₃-GO NCs/Nafion/GCE) showed a clear response for concentrations between 50 μM and 2500 μM, with a detection limit of 2.04 μM, a quantification limit of 6.78 μM, and a sensitivity of 3.08 μAμM⁻¹ cm⁻². The new probe's ability to detect TU was tested while other chemicals and interfering substances were present. Using the given methodology, the spiked real water samples were shown to be very productive in terms of recovery. A new approach has been developed that combines two different metal oxides and GO NCs, controlled through an electrochemical process, with the goal of ensuring environmental and ecological safety on a large scale. This study shows an advancement of electrochemical sensing of TU by HgO/Y₂O₃-GO NCs. The combination of mercury and yttrium oxide along with graphene oxide for better electron transfer and an increase in the surface area of the electrode, which increases its sensitivity and stability. The synergistic effect of the metal oxides and Go ensures a faster exchange of charge, which produces an excellent, sensitive, and reproducible sensor for TU detection suitable for environmental monitoring.