Sensitive detection of thiourea using binary ZnO@Co3O4 nanodisc using electrochemical method for environmental analysis

In this approach, low-dimensional nanostructure material for ZnO@Co₃O₄ nanodisc was prepared by using the wet-chemical method in the basic medium with the use of precursors. The calcined ZnO@Co₃O₄ nanodisc was initially characterized by using various conventional methods including FTIR, FESEM, BET, TEM, XPS, EDS, and XRD for functional, morphological, binding energy, elemental, crystallinity and surface area etc. For the detection of thiourea, a flat glassy carbon electrode (GCE) was fabricated with the help of a conducting coating binder (5.0 % Nafion) and used as the working electrode by electrochemical approach. Thiourea is also detected using an electrochemical sensor by a facile and sensitive technique that called the linear sweep voltammetry (LSV) during the electrochemical oxidation of thiourea in aquious phase. The results illustrate a rapid detection, good sensitivity, good selectivity, good reproducibility, lower cost, and easy fabrication method compared to conventional methods (complex assembly). The coated GCE electrode with ZnO@Co₃O₄ nanodisc using 5% nafion chemical binder was selected under optimized conditions. The sensor oxidation response exhibits a linear improvement that is enhanced with the concentration of thiourea, ranging from 0.90 to 11.24 mM. Furthermore, thiourea detection with this fabricated electrode has exhibited a higher sensitivity of 1.292 µAmM^-1cm⁻² and a lower limit of detection (LOD; 29.7 µM) as well as limit of quantification (LOQ; 90.2 µM). Furthermore, excellent selectivity, stability, repeatibility, and reproducibility were also analyzed with the optimized conditions. It introduces a new approach for the sensitive detection of thiourea with low-dimensional ZnO@Co₃O₄ nanodisc by the electrochemical approach for the safety of environmental and healthcare fields on a broad scale. This study presents an efficient method for thiourea detection utilizing ZnO@Co₃O₄ nanodisc, validated with real environmental samples, that obtained recovery (∼99.0 %) with a relative standard deviation (0.5–0.7 %RSD) measurement. Finally, the development of a low-dimensional ZnO@Co₃O₄ nanodisc with enhanced surface properties, offering improved electrocatalytic activity for thiourea detection. The sensor’s strong stability (50 cycles) and remarkable reproducibility highlight its suitability for real-world applications. The synthesis and sensor fabrication processes are facile, scalable, easy, and cost-effective, distinguishing this method from complex, resource-intensive approaches.