Series of in-fiber graphene supercapacitors for flexible wearable devices

Miniaturization and flexibility are important for portable electronic devices. Micro-fiber supercapacitors with superior mechanical flexibility significantly facilitate the large-scale integration to supplement or even replace conventional supercapacitors and batteries, especially in wearable electronic devices. This work achieves a novel bamboo-like series of in-fiber graphene supercapacitors by directly laser writing along a graphene oxide fiber. Hundreds of device units can be fabricated within minutes and the generated supercapacitors can reach a high capacitance of 14.3 mF cm⁻². More importantly, large-scale integration of the in-fiber supercapacitors into the textile can be realized by a conventionally weaving technique, demonstrating their great potential in wearable electronic devices.