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A graphene surface force balance.

Britton J, Cousens NE, Coles SW, van Engers CD, Babenko V, Murdock AT, Koós A, Perkin S, Grobert N - Langmuir (2014)

Bottom Line: We demonstrate the compatibility of these model surfaces with the surface force balance, opening up the possibility of measuring normal and lateral forces, including friction and adhesion, between two graphene sheets either in contact or across a liquid medium.The conductivity of the graphene surfaces allows forces to be measured while controlling the surface potential.This new apparatus, the graphene surface force balance, is expected to be of importance to the future understanding of graphene in applications from lubrication to electrochemical energy storage systems.

View Article: PubMed Central - PubMed

Affiliation: Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom.

ABSTRACT
We report a method for transferring graphene, grown by chemical vapor deposition, which produces ultraflat graphene surfaces (root-mean-square roughness of 0.19 nm) free from polymer residues over macroscopic areas (>1 cm(2)). The critical step in preparing such surfaces involves the use of an intermediate mica template, which itself is atomically smooth. We demonstrate the compatibility of these model surfaces with the surface force balance, opening up the possibility of measuring normal and lateral forces, including friction and adhesion, between two graphene sheets either in contact or across a liquid medium. The conductivity of the graphene surfaces allows forces to be measured while controlling the surface potential. This new apparatus, the graphene surface force balance, is expected to be of importance to the future understanding of graphene in applications from lubrication to electrochemical energy storage systems.

No MeSH data available.


Related in: MedlinePlus

(a) Illustration of gSFB lens structure detailing thefive-layerinterferometer setup consisting of epoxy–graphene–film–graphene–epoxy.(b and c) Two sets of graphene lens surfaces showing the detrimentaleffect of positive protrusions on finding a contact point.
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fig2: (a) Illustration of gSFB lens structure detailing thefive-layerinterferometer setup consisting of epoxy–graphene–film–graphene–epoxy.(b and c) Two sets of graphene lens surfaces showing the detrimentaleffect of positive protrusions on finding a contact point.

Mentions: We present a newfive-layer interferometer setup, analogous to the traditional mica–film–micainterferometer used in SFB, consisting of epoxy–graphene–film–graphene–epoxy(where the film can be air, vapor, or a liquid), as shown in Figure 2a. The key to the success of the graphene-coatedlenses for force measurement and interferometry are (i) chemical cleanliness(e.g., absence of polymer residues from graphene transfer) and (ii)absence of “positive protrusions” in the graphene, asindicated in panels b and c of Figure 2. Thiswas achieved by way of a new double-transfer procedure, making useof an atomically smooth and clean mica surface as a template. Individualsteps in this double-transfer procedure were as follows (see the Materials and Methods for full details, and a schematicof the procedure is shown in Figure 3):


A graphene surface force balance.

Britton J, Cousens NE, Coles SW, van Engers CD, Babenko V, Murdock AT, Koós A, Perkin S, Grobert N - Langmuir (2014)

(a) Illustration of gSFB lens structure detailing thefive-layerinterferometer setup consisting of epoxy–graphene–film–graphene–epoxy.(b and c) Two sets of graphene lens surfaces showing the detrimentaleffect of positive protrusions on finding a contact point.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4386928&req=5

fig2: (a) Illustration of gSFB lens structure detailing thefive-layerinterferometer setup consisting of epoxy–graphene–film–graphene–epoxy.(b and c) Two sets of graphene lens surfaces showing the detrimentaleffect of positive protrusions on finding a contact point.
Mentions: We present a newfive-layer interferometer setup, analogous to the traditional mica–film–micainterferometer used in SFB, consisting of epoxy–graphene–film–graphene–epoxy(where the film can be air, vapor, or a liquid), as shown in Figure 2a. The key to the success of the graphene-coatedlenses for force measurement and interferometry are (i) chemical cleanliness(e.g., absence of polymer residues from graphene transfer) and (ii)absence of “positive protrusions” in the graphene, asindicated in panels b and c of Figure 2. Thiswas achieved by way of a new double-transfer procedure, making useof an atomically smooth and clean mica surface as a template. Individualsteps in this double-transfer procedure were as follows (see the Materials and Methods for full details, and a schematicof the procedure is shown in Figure 3):

Bottom Line: We demonstrate the compatibility of these model surfaces with the surface force balance, opening up the possibility of measuring normal and lateral forces, including friction and adhesion, between two graphene sheets either in contact or across a liquid medium.The conductivity of the graphene surfaces allows forces to be measured while controlling the surface potential.This new apparatus, the graphene surface force balance, is expected to be of importance to the future understanding of graphene in applications from lubrication to electrochemical energy storage systems.

View Article: PubMed Central - PubMed

Affiliation: Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom.

ABSTRACT
We report a method for transferring graphene, grown by chemical vapor deposition, which produces ultraflat graphene surfaces (root-mean-square roughness of 0.19 nm) free from polymer residues over macroscopic areas (>1 cm(2)). The critical step in preparing such surfaces involves the use of an intermediate mica template, which itself is atomically smooth. We demonstrate the compatibility of these model surfaces with the surface force balance, opening up the possibility of measuring normal and lateral forces, including friction and adhesion, between two graphene sheets either in contact or across a liquid medium. The conductivity of the graphene surfaces allows forces to be measured while controlling the surface potential. This new apparatus, the graphene surface force balance, is expected to be of importance to the future understanding of graphene in applications from lubrication to electrochemical energy storage systems.

No MeSH data available.


Related in: MedlinePlus