Bulk Production of Faceted Graphene Oxide and Graphene ...€¦ · Graphene Flagship11/10/18...

Bulk Production of Faceted Graphene Oxide and Graphene Platelets: Properties and Applications

Graphene Flagship 11/10/18 www.granphnanotech.com

Who are we

� Technological trademark for supplying high quality single-layer graphene products

� Alliance of Grupo Antolin Ingenieria and the University of Alicante

– Grupo Antolin, Spanish company of the automotive sector,

with important nanotechnology investments (CNFs)

– University of Alicante, partner for 8 years in CNFs’ projects

� We produce graphene oxide from Helical Ribbon Carbon Nanofibers by a patented method.


Graphene synthesis

Graphene

Mechanical exfoliation

Novoselov et al. (2004)Loyta et al. (2009)

Epitaxial growth

CVD on metal substrates (Ni, Pt, TiC, Cu):

Land et al. (1992), Nagashima et al. (1993)

Xuesong Li et al. (2009)

Thermal decomposition of SiC:

van Bommel et al. (1975), Forbeaux et al. (1998)

GRAPHITE

Chemical methods

Graphite IntercalatedCompounds (GIC)/

Graphite OxideBrodie (1860), Staudenmaier (1898),

Hummers & Offeman (1956)


Graphene Oxide and Graphene

Natural Graphite

Hummers

GO

Ultrasonication

GrapheneOxide (G-O)

rG-O

Complete exfoliation not possible. Low yield

Separation Exfoliated Graphene Oxide fromExfoliated Graphite Oxide by ultracentrifugation

ReductionChemical/Thermal

Stankovich et al. Carbon (2007)

CarbonNanotubes

Kosynkin et al. Nature (2009)


What is GRAnPH

Conventional Nano aproachGRAnPH

Stankovich et al, Carbon (2007)

Kosynkin et al, Nature (2009)

GRAPHITE CNTHELICAL-RIBBON CNF

Varela-Rizo et al, Carbon (2010)

GRAnPH is graphene nanoplatelets produced by chemical oxidation from HR-CNF


Helical-ribbon CNFs

Floating catalyst CVD synthesis

� Ni source/Natural gas/S compound

� High temperatures, > 1000ºC


Helical ribbon-CNFs

� Circular cross-section � Diameter around 60 nm � Wide hollow core

<

Continuous ribbon rolled along the fiber axis

Helical ribbon-CNF

Vera-Agullo et al, Carbon (2009)


5 layers

Helical-ribbon CNFs

Vera-Agullo et al, Carbon (2009)


How is GRAnPH produced

GANF

ModifiedHummers

GO

Sonication

GRAnPH oxide

KMnO4/H2SO4 Exfoliation

ReducedGRAnPH

Reduction

Highyield

Highyield

Chemical oxidation (unzipping the GANF CNFs) + sonication (exfoliation)

Main advantages:�Mass production of single/few layers graphene nanoplatelets�High crystalinity�Large flake area (>10 microns2)


GRAnPH -TEM


5 10 15 20 25 30 35 40 45 50

5 10 15 20 25 30 35 40 45 50

GANF

GRAnPH oxide

2θ

Inte

nsity

(a.u

.)

GRAnPH-XRD


GRAnPH -Raman514 nm


GRAnPH -Raman

Raman shift (cm-1)

633 nm


GRAnPH -Raman

Ferrari et al. PRL 2006 2D peak

Sample 2D (cm-1)number of

layers

GANF 2655 3-5

Granph Ox 2646 1-2

633 nm

Gupta et al. Nano lett 2006

Ferrari et al. PRL 2006

Graf et al. Nano lett 2007

Eda et al. Nature 2008

2D peak


GRAnPH - XPS

GANF

GRAnPH oxide Reduced GRAnPH

C=C

C-O

C=C

COOH

C-O, epoxyC=O

C/O =1.38

Binding Energy (eV)

Binding Energy (eV)

C/O = 5 Chemical

C/O = 14 Thermal


GRAnPH products

GRAnPH Chemically reduced

GRAnPH oxide suspensions

GRAnPH Thermally reduced

� Solvents: � Water� Acetone� THF� Isopropanol


GRAnPH products

GRAnPH oxide suspensions are highly stable at manysolvents (no surfactant)

Chemically reduced GRAnPH only in water (with NH3) Or surfactants are required (not assured individual layers)


GRAnPH applications

Electronic

� Touch panels

Energetic

� Supercapacitors� Solar cells� Batteries

Structural

� Polymer nanocomposites

Medical

� Drug delivery

Aligned over substrate

Bulk Production of Faceted Graphene Oxide and Graphene ...€¦ · Graphene Flagship11/10/18...

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