Flexible Laser-Reduced Graphene with Gradient-Wrinkled Microstructures for Piezoresistive Pressure Sensors

Abstract

Pressure sensors for monitoring human motion are gaining increasing attention, and wearable devices with good flexibility and high sensitivity are urgently needed in the field of motion monitoring. Here, a graphene-based pressure sensor was fabricated by combining prestretching and laser reduction strategy. This method not only gives the graphene oxide layer a gradient-wrinkled structure but also introduces a swelling porous structure into it. The multilevel microporous gradient-wrinkled structure provides the sensor with a broad detection range (33 Pa–6.67 kPa), a low detection limit (33 Pa), and high sensitivity (125.9 ± 10.8 kPa–1). Furthermore, the sensor has good mechanical stability and a short response time. More importantly, the potential application of the prepared sensor in monitoring a wide range of motion is demonstrated, such as finger and wrist flexion movements.