Making conductive graphene yarn in bulk

Abstract

A fast and easy method to produce conductive graphene yarn in bulk could open the door to mass production of wearable textile electronics (ACS Nano 2019, DOI: 10.1021/acsnano.9b00319). Nazmul Karim and Kostya S. Novoselov of the University of Manchester and colleagues made the flexible, washable yarn using an industrial dyeing process capable of producing 1,000 kg of the yarn in about half an hour, they say. The key is a new graphene-based dye. To make it, the researchers first dispersed graphene oxide flakes in water, then used ascorbic acid and sodium hydrosulfite to partially reduce the flakes to graphene. Next, they added polymers to the solution to prevent the flakes from clumping. They dyed a hank of cotton yarn with this solution using a lab-scale replica of a commercial yarn-dyeing machine. The partially reduced graphene oxide flakes retain some oxygen-containing functional groups that bond with the cellulose in the cotton,