Impedimetric multifunctional Sensor Based on Rubber-CNTs-orange Dye Nanocomposite Fabricated by Rubbing-in Technology

This study presents the fabrication and investigation of rubber-carbon nanotubes-orange dye (rubber-CNTs-OD) nanocomposite based resistive and impedimetric sensors. These shockproof multifunctional sensors may be used for displacement, pressure, force, humidity and temperature sensing. Rubbing-in technology was used to fabricate the coplanar sensors on rubber substrates of dimensions 12x5x5 mm3. In the middle of the substrates, the OD-CNTs mixture (1:1 wt.%) was rubbed-in to make 3 mm wide and 12-18 μm deep active layer. On both sides of the active layer the rubber-CNTs layers were formed, that act as conductive electrodes. The length, width and the thickness of the electrodes were 4-5 mm, 5 mm and 12-18 μm, respectively. The resistance and the impedance of the sensors decreased under the effect of compressive displacement, pressure, humidity and temperature. These reductions were -43 Ω/μm to -73 Ω/μm, -3950 Ω-cm2/kgf to -6008 Ω-cm2/kgf, -187 Ω/%RH to -981 Ω/%RH and -216 Ω/°C to -270 Ω/°C, respectively. The force (in perpendicular direction to the length) causes to increase the resistance and impedance (60 Ω/gf to 300 Ω/gf). The probable reasons of the observed changes in the resistance and impedance of the sensor have been described.