Light-controllable dispersion and recovery of graphenes and carbon nanotubes using a photo-switchable surfactant

Thomas Malcolm McCoy, Amelia Liu, Rico Tabor

Research output: Contribution to journalArticleResearchpeer-review

21 Citations (Scopus)


The aqueous dispersibility of carbon-based nanomaterials, namely graphene oxide (GO), reduced graphene oxide (rGO) and carbon nanotubes (CNTs), can be controlled by light via the photoisomerisation of a photoswitchable surfactant molecule adsorbed to the surface of these materials. By incorporating a cationic azobenzene photosurfactant into these systems, GO, rGO and CNT dispersions can be separated and redispersed on command utilising UV radiation at 365 nm, whereby the surfactant molecules change from the trans to the cis isomer. This increases their aqueous solubility and in turn, alters their adsorption affinity for the GO and rGO sheets such that the ratio of free to adsorbed surfactant molecules changes significantly, allowing for reversible phase separation of the colloids. These effects present a unique method for controlling the dispersion behaviour of two-dimensional nanomaterials using light as a clean and low energy external stimulus.

Original languageEnglish
Pages (from-to)6969-6974
Number of pages6
Issue number13
Publication statusPublished - 7 Apr 2016

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