CARBON NANOTUBES
Enzo MennaDipartimento di Chimica OrganicaUniversità 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.
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
hν, 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
R2
R1-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
