A highly sensitive and wearable pressure sensor based on conductive polyacrylonitrile nanofibrous membrane via electroless silver plating

Abstract

The flexible and wearable capacitive pressure sensors are widely used in healthcare monitoring, robotics manufacture and militaryequipment. These types of highly sensitive pressure sensors can be realized by designing micro-structure electrodes or dielectric layers on a wearable smart device. Herein, we prepare a flexible and conductive electrode through electrospinning of palladium ions (Pd2+)/polyacrylonitrile (PAN) solution and followed by electroless plating of the hybrid nanofibrous membranes. The FESEM images showed that the obtained conductive nanofibrous membrane was covered by a coral-like silver layer with porosity benefiting for excellent electrical conductivity. Based on the superior performance, it is used as the electrodes and jointly assembled into a full microporous structure sensor with the high-mesh nylon netting. Benefitting from the dramatically alterable contact area of the electrode and the good dielectricity of nylon netting, the as-prepared sensor exhibits a high sensitivity of 1.49 kPa−1, a fast response time of 48 ms, low hysteresis of 7.55% and stable durability over 1000 cycles. Besides, practicalhuman motions’ detection is carried out by this wearable pressure sensor. The simulation of the finite elemental analysis is used to explain the mechanism of the sensor. This fabrication method is facile, low-cost, and less metal pollution, which may provide an insight to design microstructures for improving the performance, and imply an accessible prospect in the industrialization of sensors.