CARBON NANOTUBES

Enzo MennaDipartimento di Chimica OrganicaUniversit di Padovawww.chimica.unipd.it/enzo.menna

Winter School on Organic Reactivity (WISOR 2003) Bressanone (BZ) - Italy

Nanotechnologies: working at atom scale

The beginning

"The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom.

(R. Feynman, 1959)

CARBON ALLOTROPES

zig-zag armchair

Structure

Synthesis

CO + CO C(s) + CO2

CarbonMetal

growingMWNT

substrate

Carbon

Carbon

PLV

HiPCO

10.5 %

1 %

Purification

MWNT: 1800 GPa

Mechanical properties

Tuned by:- length- helicity- number of walls- defects and kinks

Nanotubes can be:- 1-D conductors- 2-D conductors- semiconductors

Electrical properties

P. G. Collins et al. Science 278, 100 (1997)

Physical investigations

TEM imaging

Manipulation

Chemistry at the Open Ends of SWNTs

cuttingH2SO4/ HNO3 3:1

Sonication

etchingH2SO4/H2O2 4:1

S. Niyogi, M. A. Hamon, H. Hu, B. Zhao, P. Bhowmik, R. Sen, M. E. Itkis, R. C. Haddon, Acc. Chem. Res. 2002, 35, 1105.

sonicator 2

sonicator 1

Cutting and etching

0 50 100 150 200 2500

20

40

60

80

100

Yie

ld %

Time of treatment (min)

45KHz 150 W

25KHz 300 W

Etching

RR

RR

R

R R R

R

R

RR

RRR

R

RR R

RR

R

R

R

Metal impurities

Acid treatment

PLV

HiPCO

CoNi

Cu

Fe

Amide Formation

Cl

OSOCl2 NH2R

NHR

O

O

O

H

O

O

H

70 C, 24 h , 96 h, N2

Cshortened-SWNTO

N

H

CH2CH2(OCH2CH2)nOCH3

n = 41 PEG 2000

Cshortened-SWNTO

N

H

glucosamine

Della Negra, F., Meneghetti, M., Menna, E.,Full. Nanot. C. Nanostr. 2003, 11, 25.

Pompeo, F.; Resasco, D. E., Nano Letters 2002, 2, 369.

PEG Functionalization

COOH

COOH

CONH

COOH

COOH

COOH

COOH

COOH

COOH

COOHCOOH

COClCOOH

COOH

sh-SWNT-PEG5000

Soluble nanotubes

Non-linear transmittance of sh-SWNT-PEG (solid squares) and ofsuspended SWNT (open circles) in chloroform.

Menna, E.; Scorrano, G.; Maggini, M.; Cavallaro, M.; Della Negra, F.; Battagliarin, M.; Bozio, R.; Fantinel, F.; Meneghetti, M. Arkivoc 2003, Part 12, 64-73.

http://www.arkat-usa.org/ark/journal/2003/I12_Shine/HS-804J/HS-804J.pdf

Raman Spectroscopy

1200 1400 1600 1800

0.3

0.6

0.9

sh-SWNT-PEG pristine SWNT sh-SWNT

Inte

nsity

(A.U

.)

Raman Shift (cm-1)

200 400 600 800 1000 1200 1400 1600 1800

1400

2100

2800

SWNT HiPcoR

aman

inte

nsity

(A.U

.)

Raman shift (cm-1)

RBM

D-band

G-band

Menna, E., Della Negra, F., Dalla Fontana, M., Meneghetti, M., Phys. Rev. B 2003, 68, 193412.

SideWall reactivity

Side Wall Chemistry on SWNTs

R

NH2

R

SWNT

SWNT

diazotization

SWNT

SWNT

160 C

N

O OR

O

O NR

N N

SWNTSWNT

KOtBu, THF, -60 CNN

H BrN N

SWNT

h, 4hCF3(CF2)6CF2I

SWNT

F

arylation

nitrene cycloaddition

nucleophilic addition

radical addition

nucleophilic substitution

S. Niyogi, M. A. Hamon, H. Hu, B. Zhao, P. Bhowmik, R. Sen, M. E. Itkis, R. C. Haddon, Acc. Chem. Res. 2002, 35, 1105.

Addition of azomethine ylides

N

R1

CH2

N

R1

CHR2

R2R1-NH-CH2-CO2H + R2CHO

- CO2

N

V. Georgakilas, K. Kordatos, M. Prato, D. M. Guldi, M. Holzinger, A. Hirsch, J. Am. Chem. Soc. 2002, 124, 760-761.

DMF, reflux, 120 h

Mechanical strength (2 x diamond)

Conductivity upon doping (100 x Cu)

Thermal resistance

Gas storage

Nanotube-based materials

Devices throughstructure modifications.

Nanotubes for electronics

Field Effect Transistor:Dekker et al. Nature 393, 49 (1998)

Nanotubes as FET

Nano-circuits

P. C. Collins, M. S. Arnold, P. Avouris, Science 2001, 292, 706-709

Nanotubes for scanning microscopy

... biotin streptavidininteraction

Titration, chemical mapping ...

Scanning chemical probes

Energy generation and storage

Possible future applications

Nanotubes and molecular machines