Laser-Assisted Gaussian Microstructure Patterned PDMS Encapsulated Ti₃ C₂ T_x (MXene)-Based Pressure Sensor for Object and Touch Detection

Abstract

This work demonstrates the deposition of a Ti <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> thin film on the flexible and bio-degradable cellulose paper via vacuum filtration technique followed by encapsulation in between flexible PDMS with gaussian microstructures at the top and plain layer of PDMS at the bottom. The fabricated sensor displayed improved sensitivity of 2.65 kPa <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> in comparison to the sensitivity (1.53 kPa <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> ) calculated with unpatterned PDMS encapsulation. The enhancement of sensitivity with microstructured PDMS as force transfer layer was achieved due to quick escalation in contact area even under the application of small external pressure because of the uniform distribution of the pressure by Gaussian patterned morphology. The rise time and fall time of the fabricated sensor were found to be 400 msec and 100 msec respectively. The fabricated sensor was also utilized to detect the unknown location and position of the object using a 4 ×4 matrix array. Further, the fabricated sensor was used to demonstrate the human-machine interaction utilizing the smart glove and also an alteration in the brightness of a LED by exerting external pressure on the sensor. The successful demonstration of cost-effective, flexible Ti <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2 </sub> T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</sub> /cellulose paper pressure sensor has shown innovative applications in the field of security, the educational sector, artificial limbs, etc.