Graphene for Optical Limiting Applications Pramod Gopinath Indian Institute of Space Science and Technology Valiamala Thiruvananthapuram 695 547 Annual Photonics Workshop February 28 2014 ID: 277692
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Slide1
Hybrids with Graphene for Optical Limiting Applications
Pramod Gopinath
Indian Institute of Space Science and TechnologyValiamala, Thiruvananthapuram 695 547Slide2
Annual Photonics Workshop – February 28, 2014IIST…Slide3
Annual Photonics Workshop – February 28, 2014 Graphene
– an Introduction Methods of Graphene
Preparation Characterization of Graphene Optical Limiting Graphene
Graphene-C60
Hybrid
Polyaniline-Graphene
Hybrid
ZnO-Graphene
Hybrid
Conclusion
Outline of the talkSlide4
2010 Nobel Prize for Physics for ground breaking experiments regarding the two dimensional material graphene
Konstantin Novoselov
and Andre Geim Centre for Mesoscience and Nanotechnology and School of Physics and Astronomy, University of Manchester
Annual Photonics Workshop – February 28, 2014Slide5
Annual Photonics Workshop – February 28, 2014Fullerene
0 D
Nanotube 1 DGraphite Sheet 3 D
A. K. Geim & K. S.
Novoselov
. The rise of
graphene
.
Nature Materials
Vol
. 6
,183-191 (2007)
Graphene
Sheet (2 D monolayer of carbon
atoms)Slide6
Annual Photonics Workshop – February 28, 2014Properties of Graphene
Electronic Properties – High electron mobility (230,000 cm2/Vs)
Thermal Properties - Thermal Conductivity ( 3000 W/mK)Mechanical Properties – Strength (130 GPa), Young’s modulus (~1.3 TPa)
Optical Properties – 2.3% absorption of visible light
Quantum Hall Effect – minimum Hall conductivity ~ 4 e
2
/hSlide7
Annual Photonics Workshop – February 28, 2014Preparation of Graphene
Top down approach from Graphite
Micromechanical exfoliation Creation of colloidal suspensionsBottom up approach from carbon precursors CVD
Organic synthesis Epitaxial growth on insulating substratesSlide8
Annual Photonics Workshop – February 28, 2014Preparation of Graphene
Micromechanical exfoliation Slide9
Annual Photonics Workshop – February 28, 2014Preparation of Graphene
Graphite flakes are combined with sodium
cholate in aqueous solutionGreen and Hersam, Nano Letters, 9, 4031 (2009)Slide10
Annual Photonics Workshop – February 28, 2014Preparation of Graphene
Roll based production of graphene films on copper foilSlide11
Annual Photonics Workshop – February 28, 2014Preparation of Graphene
From Carbon nano tubes
NATURE, Vol
, 458, 16 , April (2009)Slide12
Annual Photonics Workshop – February 28, 2014Preparation of Graphene
Oxidation (
Hummers’method)H2
SO4
/ KMnO
4
H
2
SO
4
/KClO
3
Or H2SO
4
/HNO
3
……………….
H
2
O
Ultrasonication
(exfoliation)
Graphite Oxide
Graphene
Oxide
monolayer or few layers
Fuctionalization
(for better dispersion
)
Chemical reduction to restore graphitic structures
Making composite with polymers
Making composite with polymersSlide13
Annual Photonics Workshop – February 28, 2014Graphene - Characterization
Optical Microscopy
Image of Single, Double and Triple layer Graphene on Si with a 300 nm SiO2 over layerSlide14
Annual Photonics Workshop – February 28, 2014Graphene - Characterization
Atomic Force Microscopy
Images of unreduced and chemically reduced graphene oxide nanosheets deposited from aqueous dispersions Slide15
Annual Photonics Workshop – February 28, 2014Graphene - Characterization
Flourescence Quenching Microscopy
Image showing G-O single layer deposited on a SiO2 /Si wafer applying a 30 nm thick fluorescein/PVP layerSlide16
Annual Photonics Workshop – February 28, 2014Graphene - Characterization
Transmission Electron Microscopy
Image of a single layer Graphene membraneStep from a monolayer to a bilayerSlide17
Annual Photonics Workshop – February 28, 2014Graphene - Characterization
Raman Spectroscopy
D – 1350 cm-1G – 1580 cm-12D – 2700 cm-1D band – presence of disorder in atomic arrangement or edge effectG band – in plane vibration of sp2 carbon atoms
2D band – second order Raman scatteringSlide18
Annual Photonics Workshop – February 28, 2014Nonlinear Optical Materials
Saturable Absorberswhich give increased transmittance at high optical intensities or fluences
, and are useful for pulse compression, Q-switching and mode-lockingOptical LimitersWhich give decreased transmittance, and are useful for pulse shaping, mode locking and for the protection of eyes and sensor focal-plane arraysProgress in development of Optical limiters with large NLO responses in carbon-based materials like, graphitic systems, single-walled CNTs, small
π-electron systems like fullerenes, porphyrins
and
phthalocyanines
Challenge
: Development of materials that can be processed as stable solutions or liquid dispersions that can ultimately be formed into films for practical applicationsSlide19
Annual Photonics Workshop – February 28, 2014Optical Limiting
Open aperture Z-scan technique
Sheik-B
ahae, M., et al. IEEE J. of Quantum Electron.
, 26
(4
): 760-769 (1990). Slide20
Annual Photonics Workshop – February 28, 2014Optical Limiting
where
α is the linear absorption
c
oefficient
L is the thickness of the sample
Open aperture Z-scan plot
Optical limiting plot
R. L. Sutherland, Handbook of Nonlinear Optics, second ed., Marcel Dekker, New York, 2003.
z
0
is the Rayleigh length.
R is the Fresnel reflectance of the sample surface
L
eff
is given by Slide21
Annual Photonics Workshop – February 28, 2014Slide22
Annual Photonics Workshop – February 28, 2014Slide23
Annual Photonics Workshop – February 28, 2014Slide24
Annual Photonics Workshop – February 28, 2014Slide25
Annual Photonics Workshop – February 28, 2014Graphene – C60
HybridSlide26
Annual Photonics Workshop – February 28, 2014Graphene-Polyaniline Hybrid
Alen
Heeger
A.J.MacDiarmid
H.Shirakawa
2000 Nobel PrizeSlide27
Annual Photonics Workshop – February 28, 2014Synthesis of graphite oxide (GO)
Low temperature modified Hummers method
CharacterizationPeak position (cm-1)
Assigned vibrations
1729
C=O
stretching
1399
Carboxy
C-O stretching
1186
Epoxy C-O-C stretching
1084
Alkoxy
C-O stretching
1632
Unoxidized
C=C stretching
>3000
O-H stretching
Polyaniline-Graphite oxide hybrid – In-situ polymerization of aniline in the presence of synthesized graphite oxideSlide28
Annual Photonics Workshop – February 28, 2014
2 nm
SEM image
AF
M image
T
EM image
2 nmSlide29
Annual Photonics Workshop – February 28, 2014Synthesis of polyaniline-graphite oxide hybridIn-situ polymerization of aniline in presence of GO
Various compositions : PxGy, (x =proportion of aniline, y= proportion of GO)-
P4G1, P2G1, P1G1, and P1G2 Slide30
Annual Photonics Workshop – February 28, 2014TEM image
SEM images
HRTEM image
500 nm
Polyaniline
5 µm
P1G2
AFM
image
3.2 nm
1 nmSlide31
Annual Photonics Workshop – February 28, 2014Sample name
β cm GW
-1Isat GW cm-2
Polyaniline
5.8
2.5
GO
5.5
3.5
P4G1
8
1.5
P2G1
11
0.7
P1G1
13
0.6
P1G2
19
0.4
Nonlinear optical propertiesSlide32
Annual Photonics Workshop – February 28, 2014Polyaniline-phenylene diamine functionalized reduced graphene oxide hybrids
Synthesis of phenylene diamine modified reduced graphene oxide (GONH2)Slide33
Annual Photonics Workshop – February 28, 2014TEM image
SEM image
5 µmSlide34
Annual Photonics Workshop – February 28, 2014Synthesis of polyaniline-phenylene diamine modified
reduced graphene oxide hybrid
GONH2 to aniline ratio 1:21:12:1Slide35
Annual Photonics Workshop – February 28, 2014TEM images
SEM imageSlide36
Annual Photonics Workshop – February 28, 2014
Remyamol T
, Pramod Gopinath, Honey John. Synthesis and nonlinear optical properties of reduced graphene oxide covalently functionalised with polyaniline. Carbon 59 (2013) 308-314.
Sample name
β
cm
GW
-1
I
sat
GW
cm
-2
Polyaniline
5.8
2.5
GONH2
4.8
3.7
P2NH2G1
12
0.6
P1NH2G1
15
0.5
P1NH2G2
25
0.2Slide37
Annual Photonics Workshop – February 28, 2014Synthesis of polyaniline-reduced graphene oxide hybrid
Covalently grafted polyaniline- reduced graphene oxide hybridSlide38
Annual Photonics Workshop – February 28, 2014
SEM image
TEM imageSlide39
Annual Photonics Workshop – February 28, 2014Open aperture Z-scan plots
Optical limiting plots
Sample name
β cm GW-1
I
sat
GW cm
-2
GO
5.5
3.5
Polyaniline
9.5
2
Polyanilne
-g-
rGO
20
0.25
Remyamol T
, Pramod Gopinath, Honey John. Grafting of self assembled polyaniline
nanorods
on reduced graphene oxide for nonlinear optical application.
Synthetic Metals 185-186 (2013) 38-44. Slide40
Annual Photonics Workshop – February 28, 2014Reduced Graphene oxide-
ZnO Hybrid
Reduced graphene oxide –ZnO hybrid is synthesized by two routes: Hydrothermal Synthesis Solution precipitation techniqueSlide41
Annual Photonics Workshop – February 28, 2014Reduced Graphene oxide-
ZnO Hybrid
Zn(Ac)2
(1 mmol
)
CH
3
COOH
Polyvinylpyrrolidone
(PVP) (0.05 %)
Zn(Ac)
2
- PVP complex
NaOH
Kept in autoclave at different temperature for
7
h @ 100
o
C
(hydrothermal method)
H-
rGO
-ZnO-x
Different weight ratios of GO
Dispersed by
sonication
for
8
h Followed by stirring for 16h
ZnO/GO colloid
Stirred at room temperature for 12 h
(solution precipitation)
S-
rGO
-ZnO-xSlide42
Annual Photonics Workshop – February 28, 2014Slide43
Annual Photonics Workshop – February 28, 2014 Decrease of oxygen functional groups in hybrid
in both the samples peak at 1730 cm-1 (C=O stretching vibrations of the –COOH groups) is absent
For S-rGO-ZnO, peak at 1680 cm-1 indicate C=O in conjugation with C=C ID/I
G ratios 0.94 and 1.03 for H-rGO
-
ZnO
and S-
rGO
-
ZnO
Restacking of exfoliated
graphene
sheets are prevented by the
as-grown
ZnO
nanoparticles
IR and Raman spectra of H-
rGO
-
ZnO
and S-
rGO
-
ZnOSlide44
Annual Photonics Workshop – February 28, 2014
compared to bare ZnO and GO, hybrid shows enhanced nonlinear optical properties
photoinduced electron transfer and energy transfer For hydrothermally synthesized hybrid, more extended -conjugation results in enhanced NLO propertiesSlide45
Annual Photonics Workshop – February 28, 2014Lot of scope for further work in Hybrids as the optical limiting properties can be enhanced by suitably modifying the functionalities
ConclusionSlide46
Annual Photonics Workshop – February 28, 2014Collaborators: 1. Dr. Honey John, Department of Chemistry, IIST 2. Dr. Reji Philip, Raman Research Institute
Research Students: 1. Ms. Remyamol
T 2. Ms. Kavitha M KA word of Gratitude……Slide47
Thank you for listeningAnnual Photonics Workshop – February 28, 2014