A highly sensitive flexible pressure sensor based on laser-induced graphene and a composite dielectric structure

Abstract

Pressure sensors are widely used in aerospace, mechanics, and medical electronics. Among them, capacitive pressure sensors with diversified electrode materials and dielectric microstructures have been extensively investigated for better performance. However, current prevailing construction strategies for pressure sensors mainly involve expensive metal electrodes and the complicated fabrication process for the microstructured dielectric layer. Here, we propose a flexible capacitive pressure sensor based on laser-induced graphene (LIG) and a composite dielectric structure with a quick and straightforward fabrication method. Due to the multiple deformation properties of porous graphene and air chambers, the sensor exhibits a wide working range between 0 Pa to 10.4 kPa, high sensitivity up to 2.52 kPa-1, and a detection limit as low as 1.2 Pa. The simple but precise fabrication approach offers a reliable structure for the sensor, thereby resulting in a rapid response and excellent cycling stability. On the basis of the outstanding comprehensive performance, our pressure sensors display great potential in practical applications such as health monitoring and motion detection.