1

Macroscopic assemblies of aligned nanotubes

studied by X-ray diffraction and microdiffraction

Laboratoire de Physique des Solides (UMR CNRS 8502), bât. 510, Université Paris Sud, 91405 Orsay cédex, France

launois@lps.u-psud.fr

http://www.lps.upsud.fr/Utilisateurs/launois/

Pascale Launois

2

Vincent Pichot

PhD thesis at LPS Orsay (2003-2006)

Present address: Institut Franco-Allemand de Saint Louis (ISL) &

Institut de Physique et Chimie des Matériaux (IPCMS), Strasbourg, France

Mathieu Pinault, Martine Mayne-L’Hermite and Cécile Reynaud

Laboratoire Francis Perrin (LFP), CEA/CNRS, Saclay, France

Manfred Burghammer and Christian Riekel

ESRF, Grenoble, France

Stéphane Badaire, Pierre Miaudet, Cécile Zakri and Philippe Poulin

Centre de Recherche Paul Pascal (CRPP), CNRS, Bordeaux, France

3

Scheme

1. Introduction

2. Multi-walled carbon nanotube carpetsGrowth mechanisms

3. Single-walled carbon nanotube fibers Mechanical properties

versus structural properties

4. Conclusion

4

1. Introduction

Single-Walled carbon Nanotube (SWNT) - 1993

Diameter ~ nmLenght ~ μm

Chiralangle

Multi-Walled carbon Nanotube(MWNT)

1991

5

YEAR

ARTICLES with‘ALIGN’ and ‘NANOTUB’

in title

P. Launois and P. Poulin,Encyclopedia of Nanoscience and

Nanotechnology 4, 1 (2004)

Highly anisotropic

of aligned NTs

Exceptional propertiesElectronic properties

SWNT: semiconductor or metallic (unique)Withstand high current density ~109 A/cm2

(Cu wire: 106 A/cm2)

Field emission

NTs >> Mo tips

Mechanical properties

Young modulus Y ~ 1 TPa Tensile strain σR~ 45 GPa

(steel: Y~0.1 TPa, σR~ 2 GPa)High flexibility

Nano-devices Macroscopic samples

Collins and Avouris, Scientific American (2001)

6

High yield production

Fibers

23 μm

B. Vigolo et al, Science 290, 1331 (2000)

L.M. Ericson et al, Science 305, 1447 (2004)

P. Miaudet et al, Nanoletters 5, 2212 (2005)

Carpets/forests

cm

C. Singh et al, Chem. Phys. Lett. 372, 860 (2003)

M. Mayne-L’Hermite et al., Proceeding of the chemical vapor deposition-XVI

and EUROCVD-14, vols. 2003–2008 : p. 549 (2003)

7

Carpets/forests

Potential applications

Chemical separation and sensing

B.J. Hinds et al, Science 303, 62 (2004)

N. Grobert et al, Appl. Phys. Lett. 75, 3363 (1999)

High density magnetic storage

Very high toughness fi bulletproof vests, protective textiles

or helmets

Fibers

A.B. Dalton et al, Nature 423, 703 (2003)

570 J/g> spider

dragline silk

Strain

Stre

ss

55J/g> kevlar

P. Miaudet et al, Nano Letters 5, 2212 (2005)

Toughness

8

X-ray scattering studies(LPS - Orsay, LURE - Orsay, ESRF- Grenoble)

Carpets/forests

MWNT carpetssynthesized by

CatalyticVapour Deposition (CCVD)

Prerequesitive for development of applications:

growth mechanisms?

Fibers

SWNT/polyvinyl alcohol (PVA)fibers

Mechanical properties

versus

structural properties

- SWNT alignment

- PVA structure and alignment

- SWNT-PVA interactions

9

2. MWNT carpets

The aerosol-assisted CCVD method

850°C

M. Pinault, M. Mayne-L’Hermite, C. ReynaudLaboratoire Francis Perrin, CNRS/CEA-Saclay, France

Siliconsubstrate

NT carpet

10

ϕ=0°

y

X-rayscarpet

Si substrate

2D detector

Structure and morphology from X-ray scattering

cfc γ Fe (220)

C~3.45Å MWNT long axis: preferential orientation ^ carpet basis

(002)MWNT

V. Pichot, P. Launois, M. Pinault, M. Mayne-L’Hermite, C. Reynaud, Appl. Phys. Lett. 85, 473 (2004)

γ Fe nanowires inside nanotubes

-Confinement effect-Preferential orientation <110>

τ

[110] // NT[100] // NT[111] // NT

τ

ϕ=15°

[110]

11

Tip growth?

Growth mechanisms?

Role of iron nanowires?X. Zhang et al.,

Chem. Phys. Lett. 362, 285 (2002)

Base growth?

12

Base growth mechanism

M. Pinault, V. Pichot, H. Khodja, P. Launois, C. Reynaud and M. Mayne-L’HermiteNano Lett. 5, 2394 (2005)

B*≈ 2 min 30

B≈ 7 min 30

B*≈ 1 min 30

B≈ 7 min 30

B+F (2.5 wt%)I3

5 min5 min5 min10 min10 minT+F(5 wt%)P1

(5)(4)(3)(2)(1)

Varying parameters during the sequential injectionConstant parameterSample

Sequential growth

F=ferrocene, T=toluene, B=benzene, B*=benzene containing 13C isotope

t = 0

(1)

(2)

(3)

(4)

(5)substrate 100 µm

P1Carbon progress (using 13C detection with nuclear microprobe)

I3

13

XRD analysis: the catalyst particles

MWNT (∆)Silicon substrate (+) Particles (o) : isostructural iron oxide phases maghemite or magnetite, γ-Fe2O3 or Fe3O4

(311)

substrate10 μm

2 min

1 μm

M. Pinault, M. Mayne-L’Hermite, C. Reynaud, V. Pichot, P. Launois and D. BallutaudCarbon 43, 2968 (2005)

14

beam position (μm)

(311

) int

ensi

ty (a

.u.)

Si I1 I2

Si substrate

I1

I2

V. Pichot, P. Launois, M. Pinault, M. Mayne-L’Hermite, C. Reynaud, M. Burghammer and C. Riekel,AIP proceedings vol 786, H.Kuzmany et al. Eds., p. 158 (2005)

Iron oxyde particles:located at the carpet basis

Microdiffraction (ID13, ESRF): catalyst particles location

15

Base growth

NTiron

iron oxyde

16

Microdiffraction: NT alignment V. Pichot, P. Launois, M. Pinault, M. Mayne-L’Hermite, C. Reynaud, M. Burghammer and C. Riekel,AIP proceedings vol 786, H.Kuzmany et al. Eds., p. 158 (2005)

-180 -90 0 90 180

inte

nsity

(a.u

.)

τ (°)

HWHM

when stopping synthesis: the argon gas flushes the remaining aerosol to the reactor

aerosol injection is suddenly stopped

Crucial role of the synthesis procedure

on NT alignment

0 50 100 150

10

20

30

HW

HM

(°)

beam position (µm)

Si substrate

0 50 100 150

10

20

30

HW

HM

(°)

beam position (µm)

17

In brief…

→ Base-growth mechanism

→ Nature and structure of catalyst particles: iron oxyde maghemite or magnetite γ-Fe2O3 or Fe3O4

→ NT alignment / synthesis procedure

Interest of microdiffraction

18

3. SWNT fibers

Aqueous dispersion of SWNTwith sodium dodecyl sulfate (SDS)

is injected in a rotating solution of polyvinyl alcohol (PVA)

Condensation of NT+PVA in a ribbon

Rinsed ribbon suspended in air

FiberSWNT/PVA 50/50 wt %

PVA

Ribbon

NT+SDS

Fiber processing

B. Vigolo, A. Pénicaud, C. Coulon, C. Sauder, R. Pailler, C. Journet, P. Bernier and P. PoulinScience 290, 1331 (2000)P. Poulin, B. Vigolo, A. Pénicaud and C. Coulon, CNRS Patent 0002272 (2000)

CRPPBordeauxFrance

PVA = [ -CH2CHOH- ]n

19

Aim: to modify NT orientation in a fiberto analyze physical properties as a function of orientation

Post-synthesis treatment

ll0

Solvent

m

The fibers are rewetted in a solvent for PVA and are dried under tensile load

B. Vigolo, P. Poulin, M. Lucas, P. Launois, P. Bernier, Appl. Phys. Lett. 81, 1210 (2002)P. Poulin, B. Vigolo, P. Launois, P. Bernier, CNRS patent 0110611 (2001)

0

0

lll −

Draw ratio =

20

Structural analysis by X-ray diffraction

P. Launois, A. Marucci, B. Vigolo, P. Bernier, A. Derré and P. Poulin, J. Nanosci. Nanotechnol. 1, 125 (2001)V. Pichot, S. Badaire, P.-A. Albouy, C. Zakri, P. Poulin and P. Launois, submitted

X-rays2D detector

k0 k 2θB

Fiber

Q

Radial scan ⇒ composition of the fiber

SWNTbundles

amorphousPVA

Azimuthal scans fl orientation

HiPCO SWNT/ PVA fiberτ

21

V. Pichot, S. Badaire, P.-A. Albouy, C. Zakri, P. Poulin and P. Launois, submitted

• Distribution of orientations p(θ) z

•

0 20 40 60

15

20

25

w (°)

draw ratio (%)

from experiments from calculations

0 20 40 60

1

2

3

4

f

draw ratio (%)

from experiments from calculations

fl Two-phase model, oriented and non-oriented fractionsp(θ) = (p1(θ)+f p2)/(1+f), p1: Gaussian function (HWHM w), p2=1/(4π)

Calculations:affine model

of induced orientations at constant volume

NT orientation improved for increasing draw ratios

z’ ≡ NT long axis θ

ϕx

y

z

22

Mechanical propertiesare improved

for better nanotubes alignment

Mechanical properties

V. Pichot, S. Badaire, P.-A. Albouy, C. Zakri, P. Poulin and P. Launois, submitted

E=22GPa

σR=170MPa

23

Continuum mechanics Role of PVA neglected

T. Liu and S. Kumar, Nanoletters 3, 647 (2003)

)(cos2111)(cos22115,0

4

1

12

1221

2

21

12

122θθ ⎟

⎠⎞

⎜⎝⎛ +−++⎟

⎠⎞

⎜⎝⎛ −−+

=

Ev

GEEEEv

GE

E

E1, E2, G12 and v12 = longitudinal modulus, transverse modulus, in-plane shear modulus and Poisson’s ratio of a nanotubes bundle

For perfect alignment, Young modulus → E1/2=320 GPa >> 20 GPa measured

Agreement correct…

but not very good:

role of PVA-NT interactions?

24

Rubber

Draw ratio 300%

From P.A. Albouy, LPS, Orsay France

Cis-polyisopropene

Stearic acid

G.R. Michell , Polymer 25, 1562 (1984)

‘I(τ) may be considered to be the consequence ofsmearing or convoluting the scattering which wouldbe associated with a single orienting structure Iu(τ),

with the orientation function D(τ)’

The observed anisotropy in the scatteringmay be much smaller than

the anisotropy in the molecular orientation

τ

V. Pichot, S. Badaire, P.-A. Albouy, C. Zakri, P. Poulin

and P. Launois, submitted

HiPCO SWNT/ PVA fibers

AmorphousPVA

NT

PVA chains alignment is templated by that of NTs

Same Gaussian fit

Evidence for PVA-NT interactions

25

AmorphousPVA

NT

PVA partial

crystallisationFrom V. Pichot

PhD thesis, Université Paris XI

France (2005)

P. Miaudet, S. Badaire, M. Maugey, A. Derré, V. Pichot, P. Launois, P. Poulin and C. Zakri,Nano Letters 5, 2212 (2005)

Solvent drawing Hot drawing

Improved mechanical properties for improved alignment and PVA crystallization

E=22GPa

σR=170MPa

55J/g> kevlar

E~30GPa

σR~1600MPa

See also:Cadek et al, Nano Lett. 4, 353 (2004)Coleman et al,Adv. Func. Mat. 14, 791 (2004)

Role of the PVA structure

26

In brief…

→ Mechanical properties are improved for improved NT alignment

→ PVA alignment is templated by NTs

→ Mechanical properties depend on PVA-NT interactions

and on PVA structure

(amorphous/crystalline)

→ High toughness for hot drawn fibers

27

4. Conclusion

X-rays

Carpets Fibers

Base growth mechanism

Iron oxyde catalytic particles

Iron nanowires inside NTs

• Iron oxyde/iron?

• Iron-NT interactions?

• How to obtain αFe ferromagnetic nanowires?

NT<110>

γFe

iron oxyde

Mechanical properties improved for

improved NT alignment

Opened questions…

• PVA-NT interactions?

• Role of PVA for mechanical properties?