2D/2D Nanostructured System Based on WO₃/WS₂ for Acetone Sensor and Breath Analyzer

The main aim of this research investigation is to evaluate the acetone-sensing performance of the heterostructured nanohybrid of WO 3 /WS 2 by its constituents, two-dimensional (2D), WO 3 and WS 2 for use in biomedical to industrial-level utilization. Using a rapid chemiresistive sensor to examine the level of acetone in an individual’s exhaled breath shows potential for identifying diabetes in humans. The prepared nanosheets were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction (XRD) pattern, UV–visible spectroscopy, and Fourier transform infrared (FTIR) analysis. XPS results confirm the presence of W 4+ and W 6+ oxidation states with overlapped peaks, revealing the formation of a 2D/2D nanosheet-like system of the WO 3 /WS 2 heterostructure. Sensing results show sensor responses of 132.5 and 17.0 at acetone concentrations of 1000 and 1 ppm, respectively, signifying the utilization of this sensor device for biomedical and industrial-scale applications. The limit of detection (LOD) for the biomedical range was found to be 1.54 ppm, whereas for the industrial scale, the LOD was found to be 21.02 ppm. Exhaled breath-based analysis suggests that this sensing device can also be employed for continuous exhaled breath monitoring. For example, a WO 3 /WS 2 -based heterostructured device shows a sensor response of 98.7 to exhaled breath containing only 8 vol %, demonstrating excellent capability for continuous breath monitoring. Density functional theory (DFT) predicts the reason behind the selective detection of acetone with a sensor response of 46.98%.