Application of Titanium Carbide Films for Sweat Components Monitoring

In this study, a water-based eco-friendly solution of Titanium Carbide MXene was ultrasonically spray-coated on a Si/SiO2 substrate for the detection of sweat substances.The optimal flow rate of the solution was found to be 0.15 ml/min, and the optimal substrate temperature was 130 o C. The resulting films had a surface roughness of ~ 17 nm.Chemoresistive sensors with titanium and aluminum contacts were fabricated, and their response to some sweat components, such as MgCl2, NH3, and NaCl, was measured.The most stable and strongest response was toward MgCl2 measured from the sensors with Ti contact.The response and recovery times of chemoresistive sensors based on MXene/Ti interface were determined to be in the range 20-60 s for the MgCl2 concentration in the range 10-40 mg/mL (typically existing in the human sweat) and 30-100 s for the NH3 concentrations in the range 0.5-2 mg/mL.These measurements can be practically useful as indicators for proper electrolyte balance and hydration status, which can be correlated to health implications.