Investigation of Spray-Coated Titanium Carbide MXene Thin Films and Their Application in Biosensors

In this study, a water-based eco-friendly solution of Titanium Carbide MXene was ultrasonically spray coated on $\mathrm{Si} / \mathrm{SiO}_{2}$ substrate for the detection of sweat substances. The optimal flow rate of the solution was found to be $0.15 \mathrm{ml} / \mathrm{min}$, and the resulting films had a surface roughness of $\sim 17 \mathrm{~nm}$ and sheet resistance of $156 \Omega /$ sq. Chemoresistive sensors with titanium and aluminum contacts were fabricated and their response to $\left(\mathrm{M g C l}_{2}, \mathrm{N H}_{3}\right.$ and $\left.\mathrm{N a C l}\right)$ was measured. The most stable and strongest response was toward $\mathrm{M g C l}_{2}$ from sensors with Ti contact.