A portable electrochemical sensor based on binary transition metal oxide (CoO/ZnO) for the evaluation of eugenol in real-time samples

Abstract

We report a one-step hydrothermal synthesis route of synthesizing the binary transition metal oxide-based composite using zinc acetate and cobalt acetate precursors. A synthesized binary transition metal oxide-based composite is characterized to understand features of crystalline and structural arrangements, functionality, chemical composition, and surface morphologies using the XRD, FT-IR, XPS, FESEM, & HR-TEM techniques. The composite materials tend to show excellent morphology with spherical morphology. Owing to this, the synthesized binary transition metal oxide composite is then modified over the surface of the glassy carbon electrode (GCE) towards the electrochemical sensing of Eugenol (EUG). In this regard, the CoO/ZnO/GCE composite delivers much more improved electrocatalytic activity because of the synergistic features offered by the binary transition metal oxides due to their unique structural morphology, high surface area, and increased active sites which afford rapid electron transfer rate to the CoO/ZnO/GCE when compared to other electrodes. CoO/ZnO/GCE sensor of determining the (EUG) with a wider linear range of 0.049 – 179.8 µM possessed nanomolar level detection (LOD) of under DPV & LSV is calculated to be 4 nM & 7 nM along with sensitivity found to be 1.366 µA µM−1 cm−2 & 1.01 µA µM−1 cm−2. The proposed CoO/ZnO/GCE has better selectivity over interference studies, with practical feasibility features of repeatability, reproducibility, and storage stability. Real-time sample practical applicability with exceptional recoveries of 99 % for the clove sample and urine samples.