Research progress of strain sensor based on laser-induced graphene
Laser induced graphene(LIG)is a three-dimensional porous graphene material obtained by direct laser irradiation of carbon precursors.With the advantages of simple preparation process,arbitrary patterning,low cost and high quality,LIG has received great attention in the field of flexible strain sensors,and has been widely used in medical health,motion monitoring,human-computer interaction and other fields.In this paper,the preparation process of LIG,the structure-properties influence factors of laser parameters,carbon precursors and doping modification,and the latest development of LIG application in flexible strain sensors were introduced.The laser parameters included laser power and scanning rate,image density,focal length and atmosphere.Carbon precursors included aromatic polymers and natural materials.Doping modification included in-situ doping and post-treatment doping.It was pointed out that the development of biocompatible and biodegradable carbon precursors was an important requirement for the renewability and sustainability of electronic products.Furthermore,large deformation and fast response were the exploration goals of LIG flexible wearable sensors,and multi-functional sensor integration was the development trend of LIG flexible wearable sensors.