Rights statement: This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Nano, copyright ©2017 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/acsnano.7b01071
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Available under license: CC BY-NC: Creative Commons Attribution-NonCommercial 4.0 International License
Final published version
Licence: CC BY
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Formation of two-dimensional micelles on graphene
T2 - a multi-scale theoretical and experimental study
AU - Robinson, Benjamin James
AU - Bailey, Steven William Dennis
AU - O'Driscoll, Luke J.
AU - Visontai, David
AU - Welsh, Daniel J.
AU - Mostert, Albertus Bernardus
AU - Mazzocco, Riccardo
AU - Rabot, Caroline
AU - Jarvis, Samuel
AU - Kolosov, Oleg Victor
AU - Bryce, Martin R.
AU - Lambert, Colin John
N1 - This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Nano, copyright ©2017 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/acsnano.7b01071
PY - 2017/3/10
Y1 - 2017/3/10
N2 - Graphene and related two-dimensional (2D) materials possess outstanding electronic and mechanical properties, chemical stability and high surface area. However, to realize graphene’s potential for a range of applications in materials science and nanotechnology there is a need to understand and control the interaction of graphene with tailored high-performance surfactants designed to facilitate the preparation, manipulation and functionalization of new graphene systems. Here we report a combined experimental and theoretical study of the surface structure and dynamics on graphene of pyrene-oligoethylene glycol (OEG) -based surfactants, which have previously been shown to disperse carbon nanotubes in water. Molecular self-assembly of the surfactants on graphitic surfaces is experimentally monitored and optimized using a graphene coated quartz crystal microbalance in ambient and vacuum environments. Real-space nanoscale resolution nanomechanical and topographical mapping of sub-monolayer surfactant coverage, using ultrasonic and atomic force microscopies both in ambient and ultra-high vacuum, reveals complex, multi-length-scale self-assembled structures. Molecular dynamics simulations show that at the nanoscale these structures, on atomically-flat graphitic surfaces, are dependent upon the surfactant OEG chain length and are predicted to display a previously unseen class of 2D self-arranged ‘starfish’ micelles (2DSMs). Whilst three-dimensional micelles are well known for their widespread uses ranging from microreactors to drug-delivery vehicles, these 2DSMs possess the highly desirable and tunable characteristics of high surface affinity coupled with unimpeded mobility, opening up strategies for processing and functionalizing 2D materials.
AB - Graphene and related two-dimensional (2D) materials possess outstanding electronic and mechanical properties, chemical stability and high surface area. However, to realize graphene’s potential for a range of applications in materials science and nanotechnology there is a need to understand and control the interaction of graphene with tailored high-performance surfactants designed to facilitate the preparation, manipulation and functionalization of new graphene systems. Here we report a combined experimental and theoretical study of the surface structure and dynamics on graphene of pyrene-oligoethylene glycol (OEG) -based surfactants, which have previously been shown to disperse carbon nanotubes in water. Molecular self-assembly of the surfactants on graphitic surfaces is experimentally monitored and optimized using a graphene coated quartz crystal microbalance in ambient and vacuum environments. Real-space nanoscale resolution nanomechanical and topographical mapping of sub-monolayer surfactant coverage, using ultrasonic and atomic force microscopies both in ambient and ultra-high vacuum, reveals complex, multi-length-scale self-assembled structures. Molecular dynamics simulations show that at the nanoscale these structures, on atomically-flat graphitic surfaces, are dependent upon the surfactant OEG chain length and are predicted to display a previously unseen class of 2D self-arranged ‘starfish’ micelles (2DSMs). Whilst three-dimensional micelles are well known for their widespread uses ranging from microreactors to drug-delivery vehicles, these 2DSMs possess the highly desirable and tunable characteristics of high surface affinity coupled with unimpeded mobility, opening up strategies for processing and functionalizing 2D materials.
KW - 2D micelles
KW - surfactants
KW - graphene
KW - scanning probe microscopy
KW - molecular dynamics
U2 - 10.1021/acsnano.7b01071
DO - 10.1021/acsnano.7b01071
M3 - Journal article
JO - ACS Nano
JF - ACS Nano
SN - 1936-0851
ER -