Highly\nSensitive Flexible Piezoresistive\nPressure Sensor Developed Using Biomimetically Textured Porous Materials

Abstract

In\nrecent times, high-performance flexible\npressure sensors that can be fabricated in an environmentally friendly\nand low-cost manner have received considerable attention owing to\ntheir potential applications in wearable health monitors and intelligent\nsoft robotics. This paper proposes a highly sensitive flexible piezoresistive\npressure sensor based on hybrid porous microstructures that can be\ndesigned and fabricated using a bio-inspired and low-cost approach\nemploying the Epipremnum aureum leaf\nand sugar as the template. The sensitivity and detection limit of\nthe obtained pressure sensor can be as high and low as 83.9 kPa^–1 (<140 Pa) and 0.5 Pa, respectively. According\nto the mechanism and simulation analyses, the hybrid porous microstructures\nlower the effective elastic modulus of the sensor and introduce an\nadditional pore resistance, which increases the contact area and conductive\npath with loads, thereby contributing to the high sensitivity that\nexceeds that of traditional microstructured pressure sensors. Real-time\nmonitoring of human physiological signals such as finger pressing,\nvoice vibration, swallowing activity, and wrist pulse is demonstrated\nfor the proposed device. The high performance and easy fabrication\nof the hybrid porous microstructured sensor can encourage the development\nof a novel approach for the design and fabrication of future pressure\nsensors.