Photoelectron emission microscopy of graphene systems

Photoelectron emission microscopy of graphene systems
Surface Analysis Group
CEA‐LETI
MINATEC
Grenoble
The Nanocharacterization
Platform of MINATEC® center provides the simultaneous measurement of local work function, micron‐
scale band structure, and chemical state at high spatial and energy resolution for evaluation of graphene based thin films and devices using laboratory X‐ray & UV photoemission electron microscopy (PEEM). Contact : HoKwon KIM, [email protected]; Olivier RENAULT, [email protected]
Applications of high lateral and energy resolution imaging XPS with a double hemispherical analyser based spectromicroscope, M. Escher, K. Winkler, O. Renault, and N. Barrett, J. Electron. Spectrosc. Relat. Phenom. 2010, 0, 178–179
Microscopic correlation between chemical and electronic states in epitaxial graphene on SiC(0001ˉ), C. Mathieu, N. Barrett, J. Rault, Y. Y. Mi, B. Zhang, W. A. de Heer, C. Berger, E. H. Conrad, and O. Renault, Phys. Rev. B., 2011, 83, 235436
LEDNA
Laboratoire Edifices Nanométriques
CEA‐Saclay
Gif sur Yvette
Collab. IN, Grenoble
Study of graphene
growth by CVD on Co substrates
• Synthesis of graphene on Co substrate at low temperature and atmospheric pressure.
• Investigation of growth mechanisms: complementary characterizations and in‐
situ analysis.
Contact : MAYNE‐L’HERMITE Martine, [email protected]
Graphene growth on cobalt substrate by APCVD at low temperature: investigations of synthesis parameters and growth mechanisms, O. Duigou et al., in preparation.
Graphene
numbering
and analysis
CEMES Centre d’Elaboration des Matériaux et d’Etudes Structurales
TOULOUSE
Electron Holography is
used to precisely map the amount of Graphene layers
at the nanoscale on a graphitic stack.
It can be coupled to various other TEM signals
(HAADF ‐ chemistry, EELS ‐
spectroscopy, HREM ‐
atomic resolution...) that
are all available through
existing TEM facility
networks.
Contact : MASSEBOEUF Aurélien, [email protected]
Surface electrostatic potentials in carbon nanotubes and graphene membranes investigated with electron holography, L. Ortolani et al., Carbon 2011, 49, 1423–1429
Tri‐layer of graphene surrounded by potassium (KC36) Graphite intercalation compounds with potassium are a route to obtain graphene. By varying the excitation energy from UV to infrared, we observe resonance effects for KC36 at 2.5 eV.
Contact : Pascal PUECH, [email protected]
Resonant Raman scattering of graphite intercalation compounds KC8, KC24, and KC36, Y. Wang, P. Puech, I. Gerber and A. Pénicaud, Journal of Raman Spectroscopy
2014, 45, 219‐223.
CIMAP
Centre de Recherche
sur les ions, les Matériaux et la Photonique
Caen
Unzipping and folding of graphene
by swift heavy ions
Individual swift heavy ions were used to cut and fold graphene under grazing angle. The folded patterns have a length of several 100 nm. Defect creation in the graphene
as well as the production of hillocks in the support, which push from below on the graphene, are necessary for the patterns.
Contact : Henning LEBIUS, [email protected]
Unzipping and folding of graphene by swift heavy ions, S. Akcöltekin, H. Bukowska, T. Peters, O. Osmani, I. Monnet, I. Alzaher, B. Ban‐d’Etat, H. Lebius, M. Schleberger, Applied Physics Letters, 2011, 98, 103103
Graphene synthesis, dispersion & functionalisation
CIRIMAT
Interuniversity Research & Engineering Centre on Materials
TOULOUSE
GRAPHENE
FLAGSHIP
Contact : FLAHAUT Emmanuel, [email protected]‐tlse.fr
P. Wick, E. Flahaut, L. Gauthier, M. Prato, A. Bianco, Angewandte Chemie, 2014, accepted
TEM images of FLG (liquid exfoliation – collab. Anadolu Univ., TR) and graphene‐like nanocarbons (CCVD synthesis) for functionalisation, dispersion studies, assessment of the environmental impact, toxicity, nanocomposites, nanoelectronics, sensors, etc.
CVD growth of graphene on AlN templates on silicon
CRHEA
Centre de recherche sur
l'hétéroépitaxie et ses
applications
VALBONNE
CRHEA works since 2010 on the CVD growth of graphene with propane on semi‐
conductors substrates. One of the specificities of our method is the possibility to hydrogenate the graphene/SiC interface during growth, which finally allows to control and to improve the electronic properties of the graphene film. The good mobilities and the high uniformities of our graphene films allow to observe quantum Hall effect at the centimeter scale which is interesting for metrology. Contact: Adrien MICHON, [email protected]
Reference: Tuning the transport properties of graphene films grown by CVD on SiC(0001): Effect of in situ hydrogenation and annealing, B. Jabakhanji et al., Physical Review B, 2014, 89, 85429
ECOLAB
Laboratory of Functional Ecology and Environment
TOULOUSE
GRAPHENE
FLAGSHIP
Contact : GAUTHIER Laury, laury.gauthier@univ‐tlse3.fr P. Wick, E. Flahaut, L. Gauthier, M. Prato, A. Bianco, Angewandte Chemie, 2014, accepted
Assessment of the Environmental impact of graphene
The potential
environmental impact of graphene and nanocarbons in general is
evaluated using different
relevant biological
models such as amphibian larvae, alguae, or plants.
CVD growth of graphene on AlN templates on silicon
CRHEA
Centre de recherche sur
l'hétéroépitaxie et ses
applications
VALBONNE
Contact: Adrien MICHON, [email protected]
Reference: Graphene growth on AlN templates on silicon using propane‐hydrogen chemical vapor deposition, A. Michon et al., Applied Physics Letters, 2014, 104, 171912
CRHEA works since 2010 on the CVD growth of graphene with propane on semi‐conductors substrates. Using an external carbon source allows to grow graphene on SiC, but also on sapphire or on AlN. This work shows the possible integration of graphene both in silicon and in III‐
nitrides technologies.
Towards
arene
nanoribbons
by
organic synthesis.
CRPP
Centre de Recherche
Paul Pascal
PESSAC, BORDEAUX
A new approach to
extended
arene‐
oligocarboxylic
acid
derivatives
such
as
alkylesters
and
alkylimides has been
developed. The carboxylic
substituents allow the
tuning of the electronic
characteristics (donor or
acceptor behaviour, band
gap) as well as the
solubility.
Contact : Fabien DUROLA, durola@crpp‐bordeaux.cnrs.fr
Reference 1: Dipyreno‐ and diperyleno‐anthracenes from glyoxylic Perkin reactions, P. Sarkar, F. Durola, H. Bock, Chem. Commun., 2013, 49, 7552‐7554.
Lab logos
ICCF
Institut de Chimie de Clermont‐Ferrand
AUBIERE
Fluorination of graphene using either atomic or molecular fluorine
Fluorine chemistry to prepare graphene materials using exfoliation or fluorination/defluor
ination of fluorinated (nano)carbons
Contact : Nicolas BATISSE, nicolas.batisse@univ‐bpclermont.fr
Reference : Nano‐patterning of fluorinated graphene by electron beam irradiation, F. Withers, T. Bointon, M. Dubois, S. Russo, M. Craciun, Nano Letters, 2011, 11, 3912–3916
Organic nanomaterials and delivery
ICT
Immunopathologie et Chimie Thérapeutique
STRASBOURG
Design and development of new advanced carbon‐
based materials (carbon nanotubes, graphene, and adamantane) via their chemical functionalisation with different classes of molecules towards biomedical applications (i.e. therapy, imaging and diagnostics). Impact of these nanomaterials on health and environment.
Contact : ALBERTO BIANCO, a.bianco@ibmc‐cnrs.unistra.fr
Graphene: safe or toxic? The two faces of the medal, Bianco A, Angew. Chem. Int. Ed., 2013, 52, 4986‐97
Evidencing a mask effect of graphene oxide: a comparative study on primary human and murine phagocytic cells, Russier J, Treossi E, Scarsi A, Perrozzi F, Dumortier H, Ottaviano L, Meneghetti
M, Palermo V, Bianco A, Nanoscale, 2013, 5,11234‐47
Growth of 13C graphene by high energy carbon implantation
ICube/MaCEPV
STRASBOURG
The mechanism of thin
layers graphite (TLG)
synthesis on
monocrystalline nickel
films on MgO(111) has
been investigated by 13C
implantation followed by
annealing at 600 °C. Carbon
implanted may migrate
either to the surface or to
the interface according to
the implantation energy.
Contact : Francois LE NORMAND, francois.le‐[email protected]
Thin layers graphite obtained by high temperature carbon implantation into nickel films” G. Gutierrez, Y. Le Gall, D. Muller, F. Antoni, C. Speisser, F. Aweke, C.S Lee, C.S Cojocaru, F. Le Normand, Carbon, 2014, 66, 1–10
1. Graphene nanomesh channel:
Bandgap opening
vs
Conductance gap
IEF
Orsay
104
NEGF/TB
simulation
Drain Current, ID (µA/µm)
Institut
d'Electronique
Fondamentale
2. Strained/unstrained Graphene channel:
103
102
Pristine Graphene
VDS = 0.2 V
101
100
10-1
GNM (EG = 500 meV)
10-2
strained (  = 5%) / unstrained
junction (cond. gap = 360 meV)
10-3
10-4
-0.5
0
0.5
Gate Voltage, VGS (V)
1
Channel engineering of graphene
transistors: nanomesh and strain
We explore two strategies of channel engineering to improve GFET performance: introducing a Graphene Nanomesh
(GNM) section to open a bandgap or using a strained/unstrained junction to generate a transport gap. It allows enhancing strongly the Ion/Ioff ratio and other parameters (gD, fmax) .
Contact : Philippe Dollfus, philippe.dollfus@u‐psud.fr
Graphene nanomesh transistor with high on/off ratio and good saturation behavior , S. Berrada, V. H. Nguyen, D. Querlioz, J. Saint‐Martin, A. Alarcón C. Chassat, A. Bournel
and P. Dollfus , Appl. Phys. Lett., 2013, 103, 183509
Improving performance of graphene transistors by strain engineering , V. Hung Nguyen, H. Viet Nguyen, and P. Dollfus , Nanotechnology , 2014, 25, 165201
GRAPHENE GROWTH BY Si‐
ASSISTED EPITAXY
IEMN
Institute of Electronics, Microelectronics & Nanotechnology
Villeneuve d’Ascq
Contact : Dr. Dominique VIGNAUD, Dominique.Vignaud@univ‐lille1.fr
High‐resolution angle‐resolved photoemission spectroscopy study of monolayer and bilayer graphene on the C‐face of SiC,
E. Moreau, S. Godey, X. Wallart, I. Razado‐Colambo, J. Avila*, MC. Asensio*, and D. Vignaud, Phys. Rev. B, 2013, 88, 075406
Single and bilayer graphene was grown by Si‐
flux assisted molecular beam epitaxy (MBE) on the C‐face of SiC. The SiC
substrate induces a strong doping by charge transfer, with a Dirac point located 320 meV (resp. 190 meV) below the Fermi level for monolayer (bilayer) graphene. An energy band gap is also observed, whose width is inversely dependent on the thickness.
GRAPHENE NANORIBBON FIELD‐EFFECT TRANSISTOR
IEMN
Institute of Electronics, Microelectronics & Nanotechnology
Villeneuve d’Ascq
The fabrication and RF characterization of graphene nanoribbon
field‐effect transistors are investigated. Graphene is obtained from the thermal decomposition of (0001) 4H‐SiC. A structure with an array of GNR connected in parallel was fabricated by e‐beam lithography. The best intrinsic current gain cut‐off frequency of 60 GHz and maximum oscillation frequency of 30 GHz were achieved.
Contact : Pr. Henri HAPPY, [email protected]‐lille1.fr
60 GHz current gain cut‐off frequency graphene nanoribbon FET, N. Meng, F.J. Ferrer, D. Vignaud, G. Dambrine and H. Happy Int. J. Microwave & Wireless Technoly, 2010, 2, 441
IMN
Institute of Materials Jean Rouxel
NANTES
www.cnrs‐imn.fr
Contact : CHRIS EWELS, chris.ewels@cnrs‐imn.fr www.ewels.info
Low‐energy termination of graphene edges via the formation of narrow nanotubes, Phys. Rev. Lett. 2011, 107, 065502
Nomenclature of sp2 carbon nanoforms, I. Suarez‐Martinez, N. Grobert, C. P. Ewels, Carbon 2012, 50(3), 741
Modelling doped
and
defective
nanocarbon
DFT Modelling of new
carbon
nanostructures
(cones, scrolls, fullerenes)
to
understand
and
control edge behaviour,
defect structure, chemical
tuning
and
new
nanocarbon forms.
Graphene redox Chemistry
IMN
Controlling graphene‐
based electrode materials through chemical functionalisation to improve supercapacitance and Li‐
ion storage capabilities
Institute of Materials Jean Rouxel
NANTES
www.cnrs‐imn.fr
Voltamogramms of modified carbon electrodes (blue) and unmodified (in black) in 0.1M H2SO4 obtained at 10 mV/s scan speed.
Contact : THIERRY BROUSSE, [email protected]‐nantes.fr
Electrochemical capacitors: When the levee breaks, T. Brousse, Electrochemistry 2013 81 (10), p. 773.
Chemically converted graphene
CEA/INAC‐SCIB
Institut Nanosciences et Cryogénie
CEA/LETI
Laboratoire d’Electronique et de Technologie de l’Information
Grenoble
The researches conducted aim at synthesizing graphene from the oxidative exfoliation of graphite and then to study its reduction, functionalization and N‐
doping to produce samples of potential interest as catalyst (ORR) and Li‐ion battery anode materials.
Contact : G. Bidan, [email protected]
Nanosilicon‐Based Thick Negative Composite Electrodes for Lithium Batteries with Graphene as Conductive Additive, Nguyen, B.P.N., Kumar, N.A., Gaubicher, J., Duclairoir, F., Brousse, T., Crosnier, O., Dubois, L., Bidan, G., Guyomard, D., Lestriez, B., Advanced Energy Materials , 2013, 3, 1351–1357
CEA/INAC‐SCIB and SPSMS
Institut Nanosciences et Cryogénie
CEA/LETI
Laboratoire d’Electronique et de Technologie de l’Information
Grenoble
Growth and grafting of epitaxial graphene
The research deals with the optimization of the 6H‐
SiC sublimation protocol in order to achieve high‐
quality graphene samples for fundamental studies of the physical properties of graphene related to the functionalization with specific molecules and to the superconducting proximity effect. Contact : G. BIDAN, [email protected]
Study of annealing temperature influence on the performance of top gated graphene/SiC transistors M. Clavel, T. Poiroux, M. Mouis, L. Becerra, J.L. Thomassin, A. Zenasni, C. Lapertot, D. Rouchon, D. Lafond, and O. Faynot, Solid‐State Electronics 71, 2 (2012).
Atomic scale study of graphene flower defects
INAC/SP2M
& LITEN/DTNM
CEA
Grenoble
Contact : Hanako OKUNO, [email protected]
Reference 1: H. Okuno, P. Pochet, A. Tyurnina and J. Dijon, publication in preparation
Aberration corrected (AC) TEM imaging of flower‐
like defects formed inside a CVD grown large single crystal domain; low‐pass filtered images (maximum filtered in insets) reveal a formation of isolated islands in combinations with several types of defects. Optical Properties of Freestanding Graphene
IPCMS
Institut de Physique et Chime des Matériaux de Strasbourg
Strasbourg
Freestanding graphene monolayers are immune from substrate‐induced perturbations, and allow investigations of graphene’s intrinsic properties. By means of spatially‐resolved Raman spectroscopy, we have demonstrated that freestanding graphene layers are quasi‐ undoped
and exhibit only small built‐in strain, below 0.1%. Contact : Stéphane BERCIAUD, [email protected]
References: 1) S. Berciaud et al. Nano Letters (2009) 9, 346 2) D. Metten et al. Phys Stat. Sol. B (2013) 250, 2681 3) S. Berciaud et al. Nano Letters (2013) 13, 3517
Epitaxy of MgO
magnetic tunnel barriers on epitaxial graphene
IPCMS
Institut de Physique et Chime des Matériaux de Strasbourg
Strasbourg
Contact : D. Halley ([email protected]) & J‐F Dayen ([email protected])
References : F. Godel et al. Nanotechnology (2013) 24, 475708
AFM images of ferro‐
magnetic (FM) electrodes after annealing and Au capping. (a) Fe, (b) permalloy and (c) Co. The smaller clusters are attributed to Au capping deposited at room temperature after annealing. The average mesa height is close to 30‐35 nm as shown on profiles in insets. (d) Micro‐Raman spectrum of graphene obtained on the sample with Fe, after annealing.
Resist‐Free fabrication of CVD graphene FETs
IPCMS
Institut de Physique et Chime des Matériaux de Strasbourg
Strasbourg
Contact : Bernard DOUDIN, [email protected]
References : A. Mahmood et al., to be submitted
(a) Stencil mask pattern used to define the graphene device shape. (b) Optical image of the cross‐bar shaped graphene device with width 30 µm and length 250 µm. (c) 2D Raman map showing the ID / IG peak ratio of the device central portion. (d) Magnetoconductance
(Δσ (B) ‐ Δσ (0)) curves of the device shown in (c) with at various temperatures. Graphene‐Molecule Interface
IS2M
Institut de Science des Matériaux
de Mulhouse
MULHOUSE
* A perfect substrate in order to obtain structurally and electronically homogeneous self‐assembled molecular layers.
*Direct visualization of Molecular Orbitals.
*Possible doping of Graphene while preserving its electronic properties. Transfer of charge from/to molecule depending on its conformation.
Contact : Laurent SIMON, [email protected]
Generating Long Supramolecular Pathways with a Continuous Density of States by Physically Linking Conjugated Molecules via Their End Groups, R. Shokri et al., JACS, 2013, 135, 5693.
STM investigation of the molecular fastener effect of TTF molecules deposited on Graphene, M.N. Nair et al., submitted.
Graphene
functionalized by intercalation of Au
IS2M
Institut de Science des Matériaux
de Mulhouse
MULHOUSE
n°ANR‐2010‐BLAN‐1017
ChimigraphN
Modifications of the band structure of graphene while preserving its electronic properties: *no doping *increase of Fermi velocity *extension of van Hove Singularity
Single Au atoms intercalate above Buffer layer. They decouple Graphene from SiC
substrate and induce standing waves on Graphene. Contact : Laurent SIMON, [email protected]
High van Hove singularity extension and Fermi velocity increase in epitaxial graphene functionalized by intercalated Au clusters, M.N. Nair et al., PRB, 2012, 85, 245421.
Superlattice of resonators on ML graphene created by intercalated Au nanoclusters, M. Cranney et al., EPL, 2010, 91, 66004.
 Soft reaction conditions for Diels-Alder reaction
 Complete reversion to graphene upon heating
 Fabrication of transparent electrodes and conducting inks
Reversible covalent chemistry for the exfoliation of graphene
ISM
Institute of Molecular Science
Confocal Raman on single flake
exfoliated by
cycloaddition
TALENCE
g/L
∆
sp3 defects
corrected upon
heating
THF
CH3CN
NMP
DMF
i-PrOH
Tol.
0.014
0.012
0.020
0.044
0.008
0.028
Graphite is exfoliated in a variety of solvents using only a low‐power sonication bath by using a reversible Diels‐Alder cycloaddition that, unlike oxidation, does not generate permanent defects
Contact : Dario BASSANI, [email protected]‐bordeaux1.fr
Procede d’Exfoliation de Graphite Assiste par Reaction de Diels‐Alder , H. Bares, J.‐B. Verlhac, D. M. Bassani: Pat. N° 1357602
LaHC
Laboratoire Hubert Curien
SAINT ETIENNE
Graphene by PLD as a SERS platform Diamond‐Like Carbon film grown by pulsed laser deposition has been converted to fl‐graphene and further decorated with gold nanoparticles. The textured fl‐
graphene films with nanoscale
roughness were highly beneficial for SERS detection. The detection at low concentration of a commercial pesticide was demonstrated.
Contact : Pr Florence GARRELIE, garrelie@univ‐st‐etienne.fr Graphene‐based textured surface by pulsed laser deposition as a robust platform for surface enhanced Raman scattering applications, T. Tite, C. Donnet, A.‐S. Loir, S. Reynaud, J.‐Y. Michalon, F. Vocanson, and F. Garrelie, Applied Physics Letters (2014) 104, 041912
Sp2 materials: from
selection to growth
mechanisms
L_Sim
CEA‐INAC
GRENOBLE
Understanding possible strategies to select the sp2
sector of the configuration space of new 2D materials
is of particular importance. This question has been addressed in the case of boron fullerenes for which
the polymorphism lead to a glassy‐like behavior in the potential energy
surface.
Contact : Pascal Pochet, [email protected]
Low‐energy boron fullerenes: Role of disorder and potential synthesis pathways, P. Pochet et al. Phys. Rev. B 83, 081403(R) (2011)
Selecting boron fullerenes by cage‐doping mechanisms», P. Boulanger et al.; J. Chem. Phys. 138, 184302 (2013)
Large Scale Production of Few Layer Graphene
LCC
Laboratoire de Chimie de Coordination
Toulouse
A low cost, versatile catalytic fluidized bed CVD technique has been developed for the large scale production (10g/h on laboratory scale) of high quality few layer graphene (FLG) powder.1The process can be adapted to produce CNT+FLG hybrids in the desired composition.2
Contact : Serp, Philippe ‐ [email protected]
1: Graphene production method and graphene obtained by said method, R. Bacsa, P. Serp, WO 2013093350A1.
2: Method for producing an assembly of carbon nanotubes and graphene, J. Beausoleil, R. Bacsa, B. Caussat, P. Serp, WO 2013093358 A1. AFM
CL at 20 K Reference
Single crystal
LEM
Top Left panel: Atomic Force Microscopy images of exfoliated h‐BN layers on SiO2
6 ML
Laboratoire d’Etude
des Microstructures
8 ML
Châtillon
Structural and
optical properties of
exfoliated h‐BN layers
Top Right panel: Cathodoluminescence spectra of the same samples 10 ML
HR‐TEM
VEELS
Bottom Left panel: High Resolution Transmission Electron Microscopy image of an exfoliated BN sheet
Bottom Right Panel: Valence electron Energy Loss spectroscopy spectrum of the TEM sample.
Contact : LOISEAU, [email protected]
Excitonic recombination in h‐BN: From bulk to exfoliated layers, A. Pierret et al., Phys. Rev. B, 2014, 89, 035414
Atomic‐scale study of graphene
LEM
Laboratoire d’Etude
des Microstructures
Châtillon
Top panel : STS spectra and STM image of doped graphene with N Bottom panel : Growth of graphene from Ni surface (Monte Carlo simulations)
Contact : LOISEAU, [email protected]
Long –range interactions between N dopants in graphene, Ph. Lambin et al., Phys. Rev. B, 2012, 86, 045448
Electronic structure of vacancy resonant states in graphene: A critical review of the single‐vacancy case, F. Ducastelle., Phys. Rev. B, 2013, 88, 075413
3D graphene network by CVD on nickel foam
LGC
Chemical Engineering Laboratory
TOULOUSE
Wt. percentages as high as 15 % of 3D multi‐layers graphene networks have been produced from ethylene at 750 ‐ 850°C. Such graphene masses largely exceed the weights corresponding to carbon solubility into nickel at these temperatures, involving the existence of a continuous mechanism of graphene formation. Contact : Brigitte Caussat, [email protected]
Three Dimensional Graphene Synthesis On Nickel Foam By Chemical Vapor Deposition From Ethylene, P. Trinsoutrot, H. Vergnes, B. Caussat, Materials Science and Engineering B, 2014, Vol. 179, 12‐16.
Graphene‐based Heterojunctions for Photovoltaics
LGEP
Laboratoire de Génie
Electrique de Paris
Gif‐sur‐Yvette
2D materials present extraordinary sunlight absorption although transparent at the nanoscale. Such a high optical absorption with respect to the thicknesses involved makes this route appealing for energy conversion. We are interested in the recombination characterization and the modulation of the electronic properties in 2D heterojunctions.
Contact : Boutchich, Mohamed
Characterization of graphene oxide reduced through chemical and biological processes, M. Boutchich et al , Journal of Physics Conference Series, 2013, vol
433, 012001.
Graphene sheets by liquid phase exfoliation for electrical contact applications
LGEP
Laboratoire de Génie
Electrique de Paris
Gif‐sur‐Yvette
Graphene is a material with very high potential for technological innovation through its electrical, mechanical and thermal exceptional properties.
Obtention of graphene sheets by liquid phase exfoliation has been known for some years; we are interested in tuning the exfoliation conditions to obtain sheets with dimensions and structural properties suitable for spray‐deposition on the metallic substrates used for electrical contacts. Electrical properties are investigated at various scales.
Contact: Noel Sophie
Conductive‐probe AFM characterization of graphene sheets bonded to gold surfaces, F. Hauquier et al, APS, vol 258, Issue 7, p2920‐2926, 2012
Graphene oxide ultrathin films and new reduction and functionalization methods LICSEN
CEA, IRAMIS Saclay
We developed a new strategy to form thickness‐adjusted and ultra‐smooth films of very large and unwrinkled graphene oxide (GO) flakes. We also proposed a new localized reduction method of GO by electrogenerated
naphthalene radical anions followed by selective functionalization of the patterns. Contact : Stéphane Campidelli, [email protected]
Localized Reduction of Graphene Oxide by Electrogenerated Naphthalene Radical Anions and Subsequent Diazonium Electrografting, J. Azevedo, L. Fillaud, C. Bourdillon, J‐M. Noel, F. Kanoufi, B. Jousselme, V. Derycke, S. Campidelli, R. Cornut, J. Am. Chem. Soc. 2014
Flexible Gigahertz Transistors Derived from Solution‐
Based Single‐Layer Graphene
LICSEN
CEA, IRAMIS Saclay
We conducted the first study of solution‐based graphene transistors at GHz frequencies, and show that graphene ideally combines the required properties to achieve high speed flexible electronics on plastic substrates. It demonstrates the advantages of graphene inks over printable organic materials.
Contact : Derycke Vincent, [email protected]
Flexible Gigahertz Transistors Derived from Solution‐Based Single‐Layer Graphene, C. Sire, F. Ardiaca, S. Lepilliet, J‐W. T. Seo, M. C. Hersam, G. Dambrine, H. Happy, V. Derycke, Nano Letters 2012, 12, 1184
CVD Growth of Graphene on Platinum coated Si Wafers
CEA/DTNM/LITEN
/SEN/LSN
CEA SP2M/INAC
TEM imaging of SLG
CEA Grenoble Avenue des martyrs 38041 Contact : Jean Dijon ‐ [email protected]
Publication in preparation and at this conference (A.Tyurnina, H.Okuno, J.Dijon)
CEA Liten is currently developing graphene growth on Si wafers using Pt coating. The objective is to develop a green technology with reusable substrate to make high quality graphene layer. We are making Single Layer Graphene at relatively low temperature (700°C) and are going to upscale the process in an industrial microelectronic reactor.
LMSSMAT
Lab Mécanique des Sols, Structures et Matériaux
Châtenay Malabry
ANR Blanc Int
Reversible lithium storage capacities vs. cycle number for Fe2O3, GNs,
Fe2O3/GNs and Fe2O3@C/GNs
electrodes.
Contact : Jinbo Bai, jinbo,bai@ecp,fr
Synthesis and evaluation of carbon‐coated Fe2O3 loaded on graphene nanosheets as an anode material for high performance lithium ion batteries, G. Wang, H. Wang, S. Cai, JT. Bai, ZY. Ren, JB. Bai, Journal of Power Sources, 239, 2013, 37‐44
Quantum Hall Effect in mono‐, bi‐, and tri‐layer graphene
LNCMI
Laboratoire National des Champs Magnétiques
Intenses
TOULOUSE
Contact : ESCOFFIER Walter, [email protected]
Quantum Hall Effect in Trilayer Graphene, A. Kumar et. al., Phys. Rev. Lett., 2010, 107, 126806
By using high‐magnetic fields (up to 60 T), we observe compelling evidence of the integer quantum Hall effect in trilayer graphene. The magnetotransport
fingerprints are similar to those of the graphene
monolayer, except for the absence of a plateau at a filling factor of v=2.
Unveiling the Magnetic Structure of Graphene
Nanoribbons
LNCMI
Laboratoire National des Champs Magnétiques
Intenses
TOULOUSE
Contact : RAQUET Bertrand, [email protected]
Unveiling the Magnetic Structure of Graphene Nanoribbons, R. Ribeiro et. al., Phys. Rev. Lett., 2011, 107, 086601
We perform magnetotransport
measurements in lithographically patterned graphene nanoribbons down to a 70 nm width. We bring evidence that the magnetic confinement at the edges unveils the valley degeneracy lifting originating from the electronic confinement. Quantum simulations suggest some disorder threshold at the origin of mixing between chiral magnetic edge states and disappearance of quantum Hall effect.
Magnetic fields
for science
LNCMI
French National High Magnetic Field Laboratory Grenoble ‐ Toulouse
The LNCMI is one of the few large scale facilities in the world that generate high magnetic fields. They are used as a powerful experimental tool in physics, chemistry and biology.
Graphene and other two‐
dimensional materials are studied at the LNCMI with optical spectroscopy and electronic transport methods.
Contact : Marek POTEMSKI, [email protected]
Optical magneto‐spectroscopy of graphene‐based systems, C. Faugeras, M. Orlita, and M. Potemski, in Physics of Graphene, ed. H. Aoki, M.S. Dresselhaus, Springer series in NanoScience and Technology, 2014, p. 113
Quantum Hall effect metrology in graphene
LNE‐
uant
Laboratoire National de Métrologie et d’Essais
TRAPPES
Contact : W. Poirier, [email protected]
Can graphene set new standards ? W. Poirier and F. Schopfer, Nature Nanotechnology, 2010, 5, 171
QHE in exfoliated graphene with charged impurities: Metrological measurements, J. Guignard et al., PRB, 2012, 85, 165420
We explore the Hall resistance quantization accuracy, expected to be robust, even at 10‐9, to develop a convenient quantum resistance standard operating in conditions accessible to industrial end‐users (B<4T, T>5K). High quality material (>10000cm2V‐1s‐1,
n<1011 cm‐2) is required on large area.
LPN
Laboratoire de photonique et de nanostructure
MARCOUSSIS
LNE
Laboratoire National de Métrologie et d’Essais TRAPPES
Monolayer epitaxial graphene
on SiC(0001)
We directly demonstrate the importance of saturating the Si dangling bonds at the graphene/SiC(0001) interface to achieve high carrier mobility. Upon successful Si dangling bonds elimination, carrier mobility increases from 3 000 cm2V‐1s‐1 to > 11 000 cm2V‐1s‐1 at 0.3 K. Contact : Abdelkarim OUERGHI, [email protected]
Reference: High Electron Mobility in Epitaxial Graphene on 4H‐SiC(0001) via post‐growth annealing under hydrogen, E. Pallecchi, F. Lafont, V. Cavaliere, F. Schopfer, A. Lemaitre, D. Mailly, W. Poirier and A. Ouerghi; Scientific Reports (Accepted) Graphene‐capped InAs/GaAs quantum dots LPN
Laboratoire de photonique et de nanostructures
MARCOUSSIS
Uncapped as well as capped graphene
InAs/GaAs QDs have been studied. We gather from this that the average shifts  of QDs Raman peaks are reduced compared to those previously observed in graphene and GaAs
capped QDs. The encapsulation by graphene
makes the indium atomic concentration intact in the QDs by the reduction of the strain effect of graphene on QDs and the migration of In atoms towards the surface. Contact : Ali MADOURI ‐ [email protected]
Improved efficiency of graphene transferred on hetero structures of InAs/GaAs quantum dots. R. Othmen1, K. Rezgui, A. Cavanna, H. Arezki, F. Gunes, H. Ajlani, A. Madouri, M. Oueslati. Accepted at JAP LPN
Laboratoire de photonique et de nanostructure
MARCOUSSIS
IMPMC
Institut de minéralogie, de physique des matériaux et de cosmochimie
PARIS
Epitaxial Graphene
on SiC(0001) Grown under Nitrogen Flux: Evidence of Nitrogen‐Doped Graphene
The Nitrogen‐doped graphene exhibits large n‐
type carrier concentrations of about 4 times more than what is found for pristine graphene. This in‐situ doping method is highly attractive for the efficient incorporation of doping species into the graphene
lattice.
Contact : Abdelkarim OUERGHI, [email protected]
Towards single step fabrication of N‐doped Graphene/Si3N4/SiC heterostructures, E. Vélez‐Fort, E. Pallecchi, M. G. Silly, M. Bahri, G. Patriarche, A. Shukla, F. Sirotti and A. Ouerghi, NanoResearch, 2014, DOI 10.1007/s12274‐014‐0444‐9
Scanning tunneling microscopy of doped graphene
MPQ
Matériaux et Phénomènes
Quantiques
Scanning tunneling spectroscopy is used to probe the electronic structure of graphene at the atomic scale. On nitrogen doped graphene, the shift of the Dirac point and the formation of localized states has been revealed.
Paris
Contact : jerome.lagoute@univ‐paris‐diderot.fr
Localized state and charge transfer in nitrogen‐doped graphene, F. Joucken, Y. Tison, J. Lagoute, J. Dumont, D. Cabosart, B. Zheng, V. Repain, C. Chacon, Y. Girard, A. R. Botello‐Méndez, S. Rousset, R. Sporken, J.‐C. Charlier, and L. Henrard, Phys. Rev. B(R), 2012, 85, 161408
needed)
LPICM
Laboratoire de Physique des interfaces et des Couches Palaiseau
Contact : Costel Sorin COJOCARU, costel‐[email protected]
Carbon 66 (2014) 1‐10; Nanotechnology 23 (2012) 265603; Nanotechnology 22 (2011) 085601 Patents Ecole Polytechnique – CNRS: 2011, 2008
In‐place, transfer‐
free, low‐
temperature, (nano)graphene layers growth
Pioneer of the synthesis of graphene at the interface between a catalytic metal layer and the substrate, NanoMaDe
team at LPICM succeed to obtain centimeters scale, uniform nanocrystalline‐
graphene layers at temperatures as low as 250°C on various substrates including glass. The synthesis capacity will be extended in 2014 to substrates up to 4 inch.
Epitaxial graphene nano‐ribbon ballistic transport
Georgia Tech‐ School of Physics
Leibniz Universität
CNRS‐Institut Néel
Synchrotron Soleil
Inst. Jean Lamour
Contact : Claire BERGER
Exceptional ballistic transport in epitaxial graphene nanoribbons, J. Baringhaus et al., Nature, 2014, 506, 349.
Scalable templated growth of graphene nanoribbons on SiC , M. Sprinkle, Nature Nanotechnology, 2010, 5, 727
Nanoribbons 40nm wide
epitaxially
grown
on
sidewalls of silicon carbide
are single‐channel room
temperature
ballistic
conductors on a length
scale greater than 10µm,
owing to their annea‐led
smooth edges. Transport
is dominated by two
modes, possibly reflecting
ground state properties of
neutral graphene.
First direct observation of a nearly ideal
graphene band structure Synchrotron Soleil
ARPES (Angle Resolved
Photoemission
Spectroscopy) measured
band structure of a 10‐
layer C‐face graphene grown on the 6H‐SiC. The sample temperature is 6K. Three linear Dirac cones
are visible corresponding
to the outermost
decoupled graphene sheets.
Contact : A. Taleb Ibrahimi ‐ amina.taleb@synchrotron‐soleil.fr
M. Sprinkle, D. Siegel, Y. Hu, J. Hicks, P. Soukiassian, A. Tejeda, A. Taleb‐Ibrahimi, P. Le Fèvre, F. Bertran, S. Vizzini, H. Enriquez, S. Chiang, C. Berger, W.A. de Heer, A. Lanzara, E.H. Conrad Phys Rev Lett, 103, 226803 (2009). Nitrogen in the graphene…
SOLEIL synchrotron
HERMES & TEMPO beamlines
Paris, France
Contact : F. Sirotti fausto.sirotti@synchrotron‐soleil.fr
Epitaxial Graphene on 4H‐SiC(0001) grown under Nitrogen flux: evidence of low Nitrogen‐doping and high charge transfer. Velez‐Fort, E. et al., ACS Nano, 2012, 6(12), 10893–10900
Nitrogen doping of graphene is of great interest for both fundamental research to explore the effect of dopants on a 2D electrical conductor and applications such as lithium storage, composites, and nanoelectronic devices. The electronic properties of graphene are modified thanks to the introduction, during its growth, of nitrogen‐atom substitution in the carbon honeycomb lattice. Increasing graphene
production up to industrial scale
SOLEIL synchrotron
ANTARES beamline
Paris, France
The exceptional electrical
properties of graphene have
been discovered only 5 years
ago, but today the yield of
total production of different
types of graphene is greater
than 15 tons per year.
Scientists have created single
large polycrystalline graphene
sheets by a simple synthesis
method and comprehensively
characterized them using
“Nano
Angle
Resolved
Photoelectron Spectroscopy”.
Contact : J. Avila jose.avila@synchrotron‐soleil.fr
Exploring electronic structure of one‐atom thick polycrystalline graphene films: A nano angle resolved photoemission study, Avila J. et al., Scientific reports, 2013, 3: art.n°2439 Superconducting
graphene grown on Rhenium
A very efficient way to induce superconductivity in graphene consists in growing it directly on top of rhenium, a superconductor below 2K. Scanning tunneling microscopy and spectroscopy performed at 50 mK
unveiled a moiré pattern and a homogeneous superconducting state. Contact : CHAPELIER Claude, [email protected]
Induced Superconductivity in Graphene grown on Rhenium, C. Tonnoir, A. Kimouche, J. Coraux, L. Magaud, B. Gilles and C. Chapelier, Physical Review Letters, 2013, 111, 246805
Concentric transistors
Thales R&T, Palaiseau, France
Collaborations
Graphene
devices
Dual gate transistors
Funding
Towards high frequency devices
Contact : [email protected]
Celebi et al., Nano Lett. 2013, 13, 967−974.
Towards high frequency electronics & optoelectronics
Graphene
spintronics
Unité Mixte de Physique
CNRS/Thales
PALAISEAU
Spin
analyzer
graphene
Spintronics is a paradigm
focusing on electrons spin as information vector. Two properties of graphene are particularly
promising for spintronics: the transport of spin information with high
efficiency and the passivation of ferromagnetic electrodes
against oxydation.
Spin
source
Contact : Pierre SENEOR, [email protected]
Highly efficient spin transport in epitaxial graphene on SiC, Dlubak B., Martin MB et al., Nature Physics, 2012, 8, 557
Graphene‐passivated nickel as an oxidation‐resistant electrode for spintronics, Dlubak B., Martin MB et al., ACS Nano, 2012, 6, 10930
Institut UTINAM
Besançon
ISM
Institut des Sciences Moléculaires
Bordeaux
Reactivity of carbon multivacancies in graphene studied with the DFT method.
Periodic DFT calculations
have been performed to
study the reactivity with
respect to atmospheric
oxidants (O2, H2O, O3 and
atomic
oxygen)
of
multivacancy structures
created in graphene
sheet
by
removing
adjacent carbon atoms
(illustration here with the
adsorption of O2 on a
trivacancy site).
Contact : PICAUD Sylvain, sylvain.picaud@univ‐fcomte.fr
Structure and reactivity of carbon multivacancies in graphene, M. Oubal, S. Picaud, M.T. Rayez, J.C. Rayez, Computational and Theoretical Chemistry, 2012, 990, 159‐166.
IJL
Institut Jean Lamour
Vandœuvre‐lès‐
Nancy
Synthesis of few‐
layer graphene by solvothermal
reaction
This work aims for the synthesis of large few‐
layer graphene (FLG) samples by a solvothermal reaction between ethanol and sodium, then a pyrolysis1.
The material obtained is a mixture of amorphous carbon and FLG. The influence of some reaction parameters on this material is studied.
Contact : Sébastien FONTANA, sebastien.fontana@univ‐lorraine.fr
Gram‐scale production of graphene via solvothermal synthesis and sonication, M. Choucair, P. Thodarson, A. Stride, Nature Nanotechnology, 2009, 4, 30‐33
Reversible optical
doping of graphene
Supported
Suspended
Charge carrier density of graphene exfoliated on a SiO2/Si substrate is finely and reversibly tuned between electron and hole doping with. visible photons.
This photo‐induced doping happens under moderate laser power but requires hydrophilic substrates and vanishes for suspended graphene.
Contact : Erik DUJARDIN, [email protected]
Reversible optical doping of graphene, A. Tiberj, M. Rubio‐Roy, M. Paillet, J.‐R. Huntzinger, P. Landois, M. Mikolasek, S. Contreras, J.‐L. Sauvajol, E. Dujardin & A.‐A. Zahab, Scientific Reports 2013, 3, 2355.
Transport in perfect
edged graphene nanoribbons
Using a scanning tunnelling microscope, the electronic structure of a long and narrow graphene nanoribbon, which is adsorbed on a Au(111) surface, is spatially mapped and its conductance then measured by lifting the molecule off the surface with the tip of the microscope.
Contact :
Christian JOACHIM, [email protected]
Voltage‐dependent conductance of a single graphene nanoribbon, M. Koch, F. Ample, C. Joachim, L. Grill Nature Nanotechnology 2012, 7, 713‐717 Integrated graphene nanoribbon
electronics
Intrinsic electronic properties of graphene nanoribbons are obtained by patterning suspended graphene into crystalline edged nanoribbons with a new non‐amorphizing
non‐contaminating e‐
beam induced etching technique.
Contact : Erik DUJARDIN, [email protected]
Graphene nanoribbons patterning by focused electrons beam induced etching. M. Nunez, S. Linas, C. Soldano, P. Salles, M. Rubio‐Roy, O. Couturaud, E. Dujardin. 2014, in preparation.