MoO₃/V₂CT_x Nanocomposite-Based Wearable Sensor with High Sensitivity for Acetone and Hand Sanitizer Detection at Room Temperature with DFT Analysis

Paper-based wearable acetone sensing applications are favored for their biodegradable, environmentally friendly, robust, cost-effective, and commercialized properties. In this work, we investigated the effectiveness of MoO 3 nanosheets decorated by V 2 CT x nanocomposite (MoO 3 /V 2 CT x ) as a promising material for acetone sensing along with hand sanitizer monitoring capabilities for the protection of skin. Here, 2D V 2 CT x was etched from the MAX phase (V 2 AlC) and conjugated with 2D MoO 3 by a wet chemical method. The MoO 3 /V 2 CT x sensor demonstrates outstanding performance toward acetone detection, showing fast response/recovery time (0.83/2.55 s) at 25 ppm of acetone concentration. It was observed that the MoO 3 /V 2 CT x nanocomposite-based sensor exhibits good selectivity with long-term repeatability. At room temperature, the sensor response for MoO 3 /V 2 CT x was found to be 106.21 for the acetone concentration of 25 ppm, which is better than the sensor response of V 2 CT x of 28 at the same concentration. In this work, for monitoring hand sanitizer quality manufactured by different companies, a prototype was also made which is hand-held and very user-friendly. The MoO 3 /V 2 CT x nanocomposite structure was optimized with the density functional theory approach, and its interaction with the acetone was also conducted for a better understanding of the sensing mechanism.