Facile fabrication of flexible piezo-resistive pressure sensor array using reduced graphene oxide foam and silicone elastomer

Electronic skins have attracted significant interest due to their broad applications in our daily lives. Flexible pressure sensors form one of the essential parts of any electronic skin. Achieving high-performance electronic skins requires ways to make pressure sensor arrays with high sensitivity and good flexibility. We report on the facile fabrication of flexible piezo-resistive pressure sensor arrays with excellent mechanical stability, high sensitivity, and a wide working range (0–30 kPa) of pressure using reduced graphene oxide (rGO) on flexible PCB (FPCB). It shows a remarkable sensitivity of 0.13 kPa−1 in the pressure range < 10 kPa and 0.05 kPa−1 in the range of > 10 kPa, covering a broad spectrum of testing conditions. We demonstrated that it could provide a pressure map and intensity, giving tactile information of the pressure exerted on our prototype with a 4 × 4 array.