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Graphene adhesion under high pressure. Alfonso San Miguel J. Nicolle, D. Machon , Ph. Poncharal , O. Pierre-Louis Laboratoire de Physique de la Matière Condensée et Nanostructures Université de Lyon 1 et CNRS. Probing graphene adhesion. Measure of graphene adhesion energy.

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graphene adhesion under high pressure
Graphene adhesionunderhighpressure

Alfonso San Miguel

J. Nicolle, D. Machon,

Ph. Poncharal, O. Pierre-Louis

Laboratoire de Physique de la MatièreCondensée et Nanostructures

Université de Lyon 1 et CNRS

measure of graphene adhesion energy
Measure of graphene adhesion energy

Adhesion energy :

0.45 ± 0.02 J m−2 for monolayer graphene

0.31 ± 0.03 J m−2 for samples containing two to five graphene sheets

S.P. Koenig et al, Nature Nanotechnology 6, 543–546 (2011)

slide4

Graphene underhigh pressure

J. Nicolle, D. Machon, P. Poncharal,

O. Pierre-Louis and A. San Miguel

NanoLetters 11,3564 (2011)

graphene
Graphene

λ =647.1 nm

Bilayer

graphene raman g band in hydrostatic conditions
Graphene Raman G-band in hydrostatic conditions

Hooke law for an hexagonal system:

In-plane Biaxial deformation: (z = 0)

In-plane Triaxial deformation: (z = )

slide11

but why so … ?

BIAXIAL

TRIAXIAL

slide12

What can be expected ?

Substrat (Si+300 nm SiO2)

can the substrate tract

(at least partially) graphene ?

slide13

AFM: High-Fidelity Conformation of Graphene

to SiO2 Topographic Features (99%)

Graphene on SiO2

SiO2 substrate

rms ~ 0.35 nm

W.G. Cullen et al., PRL 105, 215504 (2010)

adhesion of a membrane on a sinusoidal surface
Adhesion of a membrane on a sinusoidal surface

Unbinding

Perfect adhesion

O. Pierre-Louis, Phys. Rev. E 78,

021603 (2008)

unbinding between n 2 and 3
Unbinding between n=2 and 3

Calculated

unbinding transition

a =(keq/kg)2

kg: typical substrate curvature

keq=(2gn/Cn)1/2is the adhesion equilibrium curvature

n : multilayer graphene adhesion energy onSiO2

Cn : bending rigidity.

slide17

BIAXIAL

TRIAXIAL

slide18

Why this difference of

~ 3 – 3.5 cm-1 GPa-1 ???

BIAXIAL

TRIAXIAL

slide19

Splitting of the bilayer 2D band:

an indication of doping

Alcohol

Argon

Predicted by: C. Attaccalite et al., Nano Letters2010, 10, 1172-1176.

slide22

High pressure induced doping

Pressure

effect

A. Das et al., Nat Nano2008, 3, 210-215.

high pressure induced doping
High pressure induced doping

n ~ 5 x1013 cm-2 at 7 GPa

(EF ~ 1 eV)

slide24

Doping effect on the G-band

Pressure

effect

Graphene : A. Das et al., Nat Nano2008, 3, 210-215.

Bilayer: A. Das et al., Phys. Rev. B 79, 155417 2009

slide26

Substrate mediated doping

by silanol groups

Si–O–Si + Alcohol → Si–O–H

Si–O–H groups as e- donors

Lee et al. J. Phys. Chem. C Lett. 111, 12504 (2007)

conclusions
Conclusions
  • Adhesion or unbinding decides on the
  • graphene pressure behavior (2D vs 3D)
  • Adhesion/unbinding transition observed between n=2 and n=3 (n =2 is different !!)
  • Extreme surface P-mediated doping in alcohol
  • in the adhesive configuration
  • Applications: pressure/stress sensors
2d band identification of the number of layers

(b)

l=647.1 nm

(a)

l=514 nm

HOPG

HOPG

n=5

n=5

n=4

n=4

n=3

n=3

n=2

n=2

n=1

n=1

2D band: Identification of the number of layers