The simple process developed by Dr Felice Torrisi at the CGC, and his collaborators, is a low-cost, sustainable and environmentally-friendly method for making conductive cotton textiles by impregnating them with a graphene-based conductive ink.
It leverages Dr Torrisi's work on the formulation of printable graphene inks for flexible electronics, using inks of chemically modified graphene flakes that are more adhesive to cotton fibres than unmodified graphene.
After the ink has been deposited onto the fabric, a heat treatment step improves the conductivity of the modified graphene. The researchers say the adhesion of the modified graphene to the cotton fibre is similar to the way cotton holds coloured dyes, which allows the fabric to remain conductive after several washes.
The ink can be made cheaply and the printed or impregnated cotton fabric retains its mechanical properties, breathable and comfortable to wear.
The researchers demonstrated the durability of the new graphene-based ink by designing a strain sensor (because the network of nanometre flakes dispersed within the fabric are highly sensitive to strain induced by motion). They showed that used as a wearable strain sensor, a simple graphene-coated smart cotton textile could reliably detect up to 500 motion cycles, even after more than 10 washing cycles in normal washing machine.
The research was supported by grants from the European Research Council's Synergy Grant, the International Research Fellowship of the National Natural Science Foundation of China and the Ministry of Science and Technology of China.
The technology is being commercialised by Cambridge Enterprise, the University's commercialisation arm.
Visit the Cambridge Graphene Centre at www.graphene.cam.ac.uk