Copper-embedded reduced graphene oxide fibers for multi-sensors

Yeo, C.S., Kim, H., Lim, T., Kim, H.J., Cho, S., Cho, K.R., Kim, Y.S., Shin, M.K., Yoo, J., Ju, S., Park, S.Y.
Journal of Materials Chemistry C, 5(48), 12825(2017)
DOI:10.1039/c7tc03637j

Abstract

Highly flexible and stretchable graphene-based fibers are one of the most synthetically challenging materials that are suitable for next-generation wearable electronics. Graphene-based fibers used in reliable wearable devices should be multifunctional and stable. Here, we report an easy-handling fabrication method for reduced graphene oxide fibers containing semiconducting CuI and metallic Cu particles (CRGO fiber). The fibers were prepared by wet spinning and hydriodic acid treatment from a CuCl2-ethylene glycol coagulating solution without pre-synthesized CuI and Cu particles. The fabricated CRGO fibers exhibited chemical sensitive/temperature insensitive or chemical insensitive/temperature sensitive characteristics, depending on the Cu concentration in the CRGO. This is the first demonstration of a highly selective chemical and temperature sensor with sensitivity-switching properties fabricated from twisted CRGO fibers comprising two fiber bundles with low and high Cu concentrations. © 2017 The Royal Society of Chemistry.