A Flexible Pressure Sensor Based on PDMS-CNTs Film for Multiple Applications

With the fast development of electronic skin, there is a great demand for wearable sensing devices. Herein, a piezoresistive sensor has been fabricated comprising a conductive film of Polydimethylsiloxane (PDMS)-carbon nanotubes (CNTs) sandwiched by two protection films of PDMS. A simple and low-cost manufacturing method has been proposed to wrap CNTs inside the flexible PDMS to obtain a soft sensor with excellent conductivity, high sensitivity, and fast response to various pressures. Additionally, films with different percentages of CNTs were compared. The results show that the film with 7% CNTs has higher conductivity and sensitivity. Moreover, the surface morphologies and microstructures of the superior PDMS-CNTs film were studied by scanning electron microscope, and sensing properties of the pressure sensor were tested. Furthermore, applications of single sensor and sensor array were studied. The results exhibit that the as-prepared pressure sensor successfully detected different human motions and recognized Morse code and words, indicating that the portable sensor can be potentially applied in wide areas such as smart devices and flexible robotics.