Publication

We have newly developed an ultra-high sensitive piezoresistive strain sensor by using laser-induced graphene (LIG) coated with nanoporous cobalt oxide for electronic skin and wearable healthcare devices. The graphene scribed by CO2 laser into polyimide (PI) film has been widely used in strain sensors due to its simple fabrication and easy patterning processes [1]. However, these strain sensors have relatively low sensitivity and narrow strain detection range. Herein, we have newly fabricated a high-performance piezoresistive strain sensor by using polyhedral structured nanoporous cobalt oxide with a large surface area and interconnected pores, which helps to increase the sensitivity and detection range of sensor. The measured sensitivities are 1177 and 39548 in the low (0 to 18 %) and high (18 to 23 %) strain detection range, respectively. Additionally, the strain sensor has an excellent durability (over 15,000 cycles) and a wide working range (~ 23 %), demonstrating the sensor can successfully detect various human body induced motions from subtle deformation such as wrist pulse to large human motion such as finger bending.