単層カーボンナノチューブとグラフェンの

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単層カーボンナノチューブとグラフェンの電子顕微鏡観察と分光

Electron Microscopy and Spectroscopy of Carbon Nanotube and Graphene

単層カーボンナノチューブとグラフェンの電子顕微鏡観察と分光

Electron Microscopy and Spectroscopy of Carbon Nanotube and Graphene

http://www.photon.t.u-tokyo.ac.jp

0 500 1000 1500

100 200 300 400

2 1 0.9 0.8 0.7

Raman Shift (cm^–1)

Intensity (arb. units)

Raman Shift (cm^–1) Diameter (nm)

5 nm Molecular Thermo-Fluid Engineering 2013

丸山茂夫

Shigeo Maruyama

東京大学大学院工学系研究科

機械工学専攻

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Length (m)

nm m mm m

Å

Wavenumber (cm^–1) Frequency (Hz)

THz GHz

Energy (eV)

eV meV

keV

Energy (J)

Temperature (K)

HeNe 633nm

Ar 488nm ArF 193nm

G

1590cm^–1

RBM 200cm^–1 YAG

1064nm

_Ar

1.67x10^–21J SEM

1keV

Microw ave 2.45GHz

Docomo 800MHz

sun 6000K

_H2–H2 3.18meV

_C–C 2.4meV

BS 12GHz

300K

SWNT absorb.

(7,5) C_1s

284.5eV Al–K

1468.6eV TEM

120keV

NHK Radio 594KHz TV 1–12ch

93–219MHz UHF 13ch

473MHz

Toky oFM 80MHz

10^–9 10^–6 10^–3 10⁰

10⁶ 10³ 10⁰

10¹⁸ 10¹⁵ 10¹² 10⁹

10³ 10⁰ 10^–3

10⁶ 10³ 10⁰

10^–15 10^–18 10^–21 10^–24

Length, Wavelength and Energy Scale

Raman

Planck

Absorb.

XPS PLE

(3)

Length (m)

m

Energy (eV)

eV

Energy (J)

Temperature (K)

HeNe 633nm

Ar 488nm ArF

193nm

G

1590cm^–1

RBM 200cm^–1 YAG

1064nm

sun 6000K

300K

(7,5)

10^–7 10^–6 10^–5 10^–4

10⁵ 10⁴ 10³ 10²

10¹⁵ 10¹⁴ 10¹³

10¹ 10⁰ 10^–1

10⁵ 10⁴ 10³

10^–18 10^–19 10^–20

Length, Wavelength and Energy Scale 2

Raman

Planck

Absorb. PLE

(4)

Length (m)

m

Energy (eV)

eV

Energy (J)

Temperature (K)

HeNe 633nm

Ar 488nm ArF

193nm

G

1590cm^–1 YAG

1064nm

sun

6000K 300K

(7,5)

10^–7 10^–6 10^–5

10⁵ 10⁴ 10³

10¹⁵ 10¹⁴

10¹ 10⁰

10⁵ 10⁴

10^–18 10^–19

Length, Wavelength and Energy Scale 3

Raman

Planck

Absorb.

PLE

(5)

Characterization of Carbon Nanotubes

Electron Microscopy

Transmission Electron Microscopy (TEM) Scanning Electron Microscopy (SEM)

Scanning Transmission Electron Microscopy (STEM) Scanning Probe Microscopy

Atomic Force Microscopy (AFM)

Scanning Tunneling Microscopy (STM) Optical Spectroscopy

Resonant Raman Scattering

Absorption Spectroscopy (UV-Vis-NIR) Fluorescence Spectroscopy

X-ray

X-ray diffraction

X-ray photoelectron spectroscopy (XPS, ESCA)

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Transmission Electron Spectroscopy

透過型電子顕微鏡

(TEM)

高分解能像

(Phase contrast)

電子線回折

(Electron diffraction)

電子線分光

(EELS, Electron energy loss spectroscopy)

末永和知，カーボンナノチューブの基礎と応用，培風館

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Transmission Electron Spectroscopy

末永和知，カーボンナノチューブの基礎と応用，培風館

Phase Contrast

Diffraction

EELS

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TEM Images of Carbon Nanotubes

S.Iijima, Nature, 354, pp.56-58 (1991).

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Individual tube diameter: 1.3 nm Spacing: 0.34 nm

Misalignments and Terminations

TEM from Smalley et al. at Rice University About 100 SWNTs

TEM Pictures of SWNT Ropes

5 nm By ACCVD

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HRTEM images of DWNTs & TWNTs HRTEM images of DWNTs & TWNTs

バンドルの

DWNTs

（直径分布は

1

～

2nm

）

2nm

Bundles of DWNTs

N. Shinohara’s Powerpoint

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Peapods

Suenaga et al., PRL 2003

Peapod with Sc₂@C₈₄ Shinohara,

培風館

(12)

Scanning Electron Spectroscopy

http://www.remus.dti.ne.jp/~kkkkwing/

Hitachi S4800,

日立ハイテクＨＰより

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Images of As-Grown Sample

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Vertically Aligned SWNTs on Quartz Substrate

Y. Murakami, S. Chiashi, Y. Miyauchi, M. Hu, M. Ogura, T. Okubo, S. Maruyama, Chem. Phys. Lett. 385 (2004) 298

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Horizontally Aligned SWNTs

200 nm (ST-cut

基板

13 h annealing)

SWNTs touching substrate

9 µm (ST-cut

基板

13h annealing)

Aligned SWNT

Zeolite

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STEM Image of Vertically Aligned SWNTs

Substrate

Amorphous Carbon Support

150 nm Slice by FIB

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Scanning Probe Microscopy

中山喜萬，カーボンナノチューブの基礎と応用，培風館

(18)

SWNTs Directly Generation on the AFM Stage

AFM image of SWNTs directly grown on silicon.

0 100 200 300

0 1 2 3

Position (nm)

Height (nm)

isolated SWNT (not bundle)

length : 100150 nm diameter : 1.32.2 nm density : 10 m^-2

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http://vortex.tn.tudelft.nl/~dekker/nanotubes.html

STM Image of Individual Atoms

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Absorption Spectra

500 1000 1500

Absorbance (arb. unit)

Wavelength (nm) (c) HiPco

Isolated

(d) HiPco Bundle

(b) On zeolite Isolated (a) On quartz

As–Grown

–20 0 2

Energy [eV]

v1

v2

c1

c2

–20 0 2

DOS

]

E₂₂ E₁₁

v1

v2

c1

c2

0.5 1 1.5 2

0 1 2 3

Nanotube Diameter (nm)

Energy Separation (eV)

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Resonance Raman Spectra of SWNTs

A.M. Rao et al, Science 275 (1997) 187

• RBM (Radial breathing Mode) – 100-400cm^-1 d_t^-1

• G-Band, (Graphite)

– 1550-1600cm^-1,Splitting d_t^-2

• BWF (Breit-Wigner-Fano) peaks d_t^-1 – 1520-1540cm^-1, Metallic SWNT

• D-band, (Disorder) depends on d_t – 1250-1350cm^-1, depends on E_laser

Electronic density of states

Diameter Selective

BWF

500 1000 1500 [cm

^-1

]

 

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Raman Spectrometer

AFM/STM

Micro and Macro Raman

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0 500 1000 1500

100 200 300 400

2 1 0.9 0.8 0.7

Intensity (arb. units)

Raman Shift (cm^–1) Diameter (nm)

Raman Scattering (Excitation 488nm)

) (

) 248

(  _₁

nm cm

d



laser

CCVD 800

G band (Tangential

Mode)

D band Radial

Breathing Mode (RBM)

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Kataura Plot

0 1 2

0 1 2 3

₀=2.9 eV, a_cc=0.144nm

2.54

±0.1eV

E^M₁₁ E^S₂₂

E^S₁₁

–2 0 2

0 1

(5,5)

(10,10)

(10,0)

(17,0)

Energy (eV)

Density of States (states/1C–atom/eV)

E₁₁ E₂₂

t cc

t

M d a d

E 11( ) 6 ₀ / E^S11(d_t)  2a_cc₀ /d_t

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Raman Spectra

100 200 300 400

1.8 2 2.2 2.4 2.6

2 1 0.9 0.8 0.7

488 nm 514.5 nm

633 nm

Intensity(arb.units)

(c) HiPco (b) On zeolite (a) On quartz

(f) HiPco (e) On zeolite (d) On quartz

(i) HiPco (h) On zeolite (g) On quartz 488 nm

514.5 nm

633 nm

* *

* * ⁰ ⁵⁰⁰ ¹⁰⁰⁰ ¹⁵⁰⁰

Intensity (arb.units)

Raman Shift (cm^–1) 488 nm

(c) HiPco

(b) ACCVD on zeolite (a) ACCVD on quartz

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Optical absorption and Raman RBM

Absorption of Isolated SWNTs

100 200 300 400

2 1 0.9 0.8 0.7

Intensity (arb.units)

Raman Shift  (cm^–1)

(d) HiPco (a) 850 °C

(b) 750 °C

(c) 650 °C Diameter (nm) by d = 248/

Diameter (nm) by d = 223.5/(–12.5) 0.6 0.7

0.8 0.9 1 2

B

500 1000 1500

Absorbance (arb.units)

Wavelength (nm)

(a) 850 °C

(b) 750 °C

(c) 650 °C

(d) HiPco

A

Raman RBM of ‘as grown’ samples

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Band Gap Fluorescence

D2O 1.1g /cm3

1.0g / cm3

SDS or NaDDBS

M. J. O’Connell et al., Science 297 (2002) 593

Strong Sonication 60min

Centrifugation 20,627g x 24h

S. M. Bachilo et al., Science 298 (2002) 2361.

InGaAs Detector

–2 0 0 2

Density of Electronic States　（arb. units）

Energy [eV]

absorption fluorescence

v₁

v₂ c₁

c₂

–2 0 0 2

Density of Electronic States　（arb. units）

Energy [eV]

absorption fluorescence

v₁

v₂ c₁

c₂

DOS (10,5)

Centrifugation 180,000g x 1h

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Photoluminescence (PL) excitation spectroscopy

(8,6) SWNT E₂₂

E₁₁

E₂₂ E₁₁

(8,6)

*** No fluorescence in metallic nanotube

Ground state

E₂₂

E₁₁

(29)

Comparison of ACCVD and HiPco

(a) ACCVD 850 ℃ (b) HiPco

(7,5) (7,6)

(8,6) (9,4)

(10,2)

(8,4) (6,5)

(12,1)

(11,3)

(7,5) (7,6)

(8,3)

(10,5)

(8,7)

(9,5) (10,3)

(11,1) (8,6)

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Photoluminescence from Individual Nanotube

0 45 90 135 180 0

0.5 1.0

PL Intensity (arb. units)

Excitation Polarization (degrees) expfit

0°

45°

90°

135°

180°

5m

Strong polarized emission: ideal 1D electronic structure

I

_PL

 |p(θ) •µ|

²

µ:dipole moment p:light polarization

θ:angle of light polarization and dipole

Collaboration with K. Matsuda (KAST, Saeki Group) (2004)

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XPS

日東分析センタ

HP

より，

http://www.natc.co.jp/index.html

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X‐ray photoelectron spectroscopy (XPS)

Characteristic

 X-ray penetrate to core e^-of atoms

 Some e^-releasing characteristic K.E. of element

 Collided electrons from inner layers : lower K.E./noise

Very surface sensitive process (~10 nm)

1000 800 600 400 200 0

0 5000 10000 15000 20000 25000 30000

294 291 288 285 282

Count per second (CPS)

Binding energy (eV) C1s

O1s C1s SUR

e^-top layer

X-Rays

Outer surface

Inner surface

e^-lower layer but no collisions

e^-lower layer w/ collisions

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Demonstration of Root Growth and Yield by XPS

Acknowledgement to Shimazu for the use of KRATOS (AXIS-NOVA) Co: 0.04 at%, Mo: 0.01 at%

C: 98.67 at%, O: 1.29 at%

Co: 0.41 at%, Mo: 0.15 at%

C: 19.65 at%, O: 79.8 at%

Co: 0.05 at%, Mo: 0.03 at%

C: 91.23 at%, O: 8.69 at%

C/M=197,300 C/M=114,000

Root Side

Tip Side Removed & Left

Metal of 1.3 nm

= 300 atoms (10,10) x 5 m

=813,005 atoms

C/M = 271000

Hatas’s SuperGrowth 0.013Fe

Supergrowth:50,000 wt%

(34)

X‐ray absorption spectroscopy (XAS)

Energy

Absorption

3d 3p 3s

2p 2s

1s

M-shell

L-shell

K-shell Valence

band

Conduction band

Also for characterization of fine structure

http://en.wikipedia.org/wiki/X-ray_absorption_spectroscopy

Synchrotron radiation

(hν⁾ θ

Current measurement

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Near‐edge X‐ray absorption fine structure (NEXAFS) of SWNTs

C. Kramberger et al., Phys. Status Solidi. B244 (2007) 3978.

out-of-plane

in-plane

XAS (arb. units)

Energy (eV)

285 290 295

C1s-π*

C1s-σ*

60°90°

60°75° 60°60°

60°45° 60°30°

60°15° 60°0°

(36)

X-Ray Diffraction

真庭豊，カーボンナノチューブの基礎と応用，培風館

SWNTs

単層カーボンナノチューブとグラフェンの