Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/238037

Title

Highly concentrated aqueous suspensions of graphene through ultrasonic exfoliation with continuous surfactant addition

Author(s)

Notley, Shannon M.

Abstract

Highly concentrated suspensions of graphene stabilized with surfactant were prepared using ultrasonic exfoliation. Concentrations of up to 1.5% w/w (15 mg/mL) were achieved through the continuous addition of the surfactant during the exfoliation process. Previous methods typically add the surfactant only once, prior to the commencement of sonication. The vast increase in the available solid-liquid interfacial area through delamination results in the rapid depletion of the surfactant from solution through adsorption. This leads to a change in the liquid-vapor surface tension outside of the optimum range for the efficient production of graphene sheets. By continuously replacing the surfactant to lower the surface tension during sonication and the production of the graphene surface area, the concentration of particles was significantly increased. Cationic, anionic, and nonionic surfactants were studied and all showed significant increases in the concentration of graphene produced using this continuous addition method.

Publication type

Journal article

Source

Langmuir, Vol. 28, no. 40 (Oct 2012), pp. 14110-14113

Publication year

2012

Keyword(s)

Graphene;  Graphene suspensions;  Surfactant;  Ultrasonic exfoliation

Publisher

American Chemical Society

ISSN

0743-7463

Publisher URL

http://dx.doi.org/10.1021/la302750e

Copyright

Copyright © 2012 American Chemical Society.

Additional information

The author acknowledges support from the Australian Research Council Future Fellowship program.

Peer reviewed