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Graphene adhesion under high pressure

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

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  1. 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

  2. Probing graphene adhesion

  3. 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)

  4. Graphene underhigh pressure J. Nicolle, D. Machon, P. Poncharal, O. Pierre-Louis and A. San Miguel NanoLetters 11,3564 (2011)

  5. Graphene Raman signal 2D G D

  6. Experimental : Raman in DAC G 2D

  7. Graphene λ =647.1 nm Bilayer

  8. G-band position with pressure(PTM: 4:1 methanol ethanol)

  9. G-band pressure slope

  10. Graphene Raman G-band in hydrostatic conditions Hooke law for an hexagonal system: In-plane Biaxial deformation: (z = 0) In-plane Triaxial deformation: (z = )

  11. but why so … ? BIAXIAL TRIAXIAL

  12. What can be expected ? Substrat (Si+300 nm SiO2) can the substrate tract (at least partially) graphene ?

  13. 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)

  14. Adhesion of a membrane on a sinusoidal surface Unbinding Perfect adhesion O. Pierre-Louis, Phys. Rev. E 78, 021603 (2008)

  15. A very familiar phenomena

  16. 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.

  17. BIAXIAL TRIAXIAL

  18. Why this difference of ~ 3 – 3.5 cm-1 GPa-1 ??? BIAXIAL TRIAXIAL

  19. Splitting of the bilayer 2D band: an indication of doping Alcohol Argon Predicted by: C. Attaccalite et al., Nano Letters2010, 10, 1172-1176.

  20. I(2D)/I(G) evolution

  21. I(2D)/I(G) evolution

  22. High pressure induced doping Pressure effect A. Das et al., Nat Nano2008, 3, 210-215.

  23. High pressure induced doping n ~ 5 x1013 cm-2 at 7 GPa (EF ~ 1 eV)

  24. 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

  25. A last question : why no-doping for n=3 in alcohol ? Substrate mediated doping !

  26. 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)

  27. 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

  28. Doping and mechanical (bi-axial, n=1,2) pressure effects

  29. (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

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