A review of wearable carbon-based sensors for strain detection: fabrication methods, properties, and mechanisms

Carbon-based flexible wearable sensors have received widespread attention due to their wide application in wearable electronics. This work reviewed the different carbon-based sensors from three aspects, such as fabrication, performance and working mechanisms. Carbon materials mainly included carbon nanotubes, graphene, carbon black and other carbon materials. In particular, carbon nanotubes and graphene can be assembled into various multiscale macrostructures to prepare various forms of flexible sensors, such as films, fibers, yarns or fabrics. Up to now, the reviewed flexible strain sensors in general exhibit high sensitivity, wide sensing range, fast response, long-term stability and durability. However, in the face of complex environmental and multifunctional integration in practical applications, wearable strain sensors need new technological breakthroughs in the preparation process, material synthesis and device integration.