227th acs bz oral presentation
TRANSCRIPT
Extinction Coefficients and Purity
of Single-walled Carbon Nanotubes
Bin Zhao
Haddon Research Group
Departments of Chemistry and
Chemical & Environmental Engineering
Center for Nanoscale Science and Engineering
University of California, Riverside
Applications of Carbon nanotubes
the needs of high purity
High strength light weight composites
AFM probes
Nano-electronic
devices
Field emission devices
Hydrogen storage
fuel cells
biology
carbon
nanotubes
Purity evaluation by using
electron microscopy (SEM)
Give non-quantitative
evaluation of the
purity of SWNTs.
Detect samples at 10-12 gram
scale.
a
c
b
0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2
Absorb
ance
(eV)
AA(S)
AA(I)
AA(N)
M11
S22
S11
Energy of Interband transition of SWNTs
-1
0
1
-1
0
1
Semiconducting
SWNTs
metallic
SWNTs
S22
S11
M11
DOS (a.u.)
DOS (a.u.)
ene
rgy (
eV
)e
ne
rgy (
eV
)
8000 10000 12000 14000 16000 180000.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
c
b
a
Abso
rban
ce
Wavenumber (cm-1)
Solution phase near-IR spectra of SWNT samples
Purity Evaluation of As-Prepared Single-Walled
Carbon Nanotube Soot by Use of Solution-Phase
Near-IR Spectroscopy
M. E. Itkis, D. E. Perea, S. Niyogi, S. M. Rickard, M. A. Hamon, H.Hu,
B. Zhao, and R. C. Haddon* Nano lett. 2003, 3, 309.
reference sample (R)
8000 10000 120000.0
0.2
0.4
REFERENCE (R)
AA(T,R)
Ab
so
rba
nce
Wavenumber (cm-1)
0.0
0.1
AA(S,R)
R
8000 10000 12000
AA(T,X)
SWNTs: 67%
CARBONACEOUS
IMPURITIES: 33%
XAA(S,X)
AA(S, R)
AA(T, R)= 0.141
AA(S, X)
AA(T, X)= 0.095
Purity of X against R = (0.095/0.141)*100% =67%
5000 10000 150000.00
0.02
0.04
0.06
0.08
0.10
0.12
Wavenumber (cm-1)
5000 10000 150000.00
0.02
0.04
0.06
0.08
0.10
0.12
M11
S22
S11
Absorb
ance
Wavenumber (cm-1)
Controlled Purification of Single-Walled Carbon
Nanotube Films by Use of Selective Oxidation and
Near-IR Spectroscopy
O2-292oC-4h
R. Sen, S. M. Rickard, M. E. Itkis, and R. C. Haddon*
Chem. Mater. 2003, 15, 4273.
AP-SWNT Oxidized SWNT
8000 9000 10000 110000.000
0.004
0.008
AA(S)=17.7
Absorb
ance
Wavenumber (cm-1)
0.00
0.02
0.04
0.06
0.08
AA(T)=278
0.00
0.02
0.04
0.06
0.08
AA(T)=67
8000 9000 10000 110000.000
0.004
0.008
AA(S) =12.8
Ab
so
rba
nce
Wavenumber (cm-1)
AA(S)/AA(T) = 0.0635 AA(S)/AA(T) = 0.191
Relative Purity (RP) = = 3.0AA(S, OX)/AA(T, OX)
AA(S, AP)/AA(T, AP)
AP-SWNT Oxidized SWNT
100
80
60
40
20
0
20
40
60
80
16M/12h16M/6h
7M/12h7M/6h3M/48h
3M/24h3M/12h
AP
Weig
ht lo
ss%
Weig
ht%
SWNT weight%
Metal weight%
Carbonaceous impurities weight%
Lost Weight%
AP-SWNT
7M/6h
15M/12hH. Hu, B. Zhao, M. E. Itkis and R. C. Haddon
J. Phys. Chem. B. 2003, 107, 13838.
Nitric Acid Purification of
Single-Walled Carbon Nanotubes
Extinction coefficient study of single-walled carbon
nanotubes and other carbonaceous materials
Solution phase NIR is a powerful tool to assess
carbonaceous purity of SWNTs.
Demonstration of the applicability of Beer’s law of
carbonaceous materials.
Effective extinction coefficient study of SWNTs and
carbonaceous materials – a way to estimate the universal
purity of SWNTs.
B. Zhou, et. al.
JPCB 2003, 107, 13588.
Absorptivity of Functionalized
Single-Walled Carbon Nanotubes
in Solution
J. A. Bahr, et. al.
Chem. Comm. 2001, 193.
Dissolution of small diameter
single-wall carbon nanotubes
in organic solvents
10000 15000 20000 250000.0
0.2
0.4
0.6
0.8
1.0
carbon black
Absorb
ance
10000 15000 20000 25000
Wavenumber (cm-1)
MWNT
10000 15000 20000 25000 30000
AP-SWNT (EA)
10000 15000 20000 250000.0
0.2
0.4
0.6
0.8
1.0
Absorb
ance purified SWNT (EA)
10000 15000 20000 25000
AP-SWNT (LO)
10000 15000 20000 25000 30000
AP-SWNT (HC)
The NIR spectra of carbonaceous materials
1 2 3
S11
M11
M11
S22
S22
S11
M11
S22
S11
HC
LO
EA
A
bsro
ba
nce
(a
.u.)
Energy (eV)
Electronic structures of SWNTs
produced by different methods
Purity of EA prepared SWNTs (against R-SWNT)
63
37
70
11
3932
116
133
113
0
20
40
60
80
100
120
140
Purity
(%
)
AP
1-E
AA
P2-E
A
AP
3-E
A
AP
4-E
A
AP
5-E
A
AP
6-E
A
P1-E
A
P2-E
A
P3-E
A
Sample AA(S) AA(T) Purity
(% of R-SWNT)
AP1-EA 101.9 1149.5 63
AP2-EA 50.2 962.2 37
AP3-EA 113.9 1162 70
AP4-EA 13.7 892.1 11
AP5-EA 60.4 1109.8 39
AP6-EA 43.2 960.1 32
P1-EA 158.5 971.6 116
P2-EA 252.3 1348.1 133
P3-EA 208.8 1304 113
The purity of LO SWNTs
Method 1:
AA(S, LO)
AA(S, LO) + AA(B, LO)= 0.066
AA(S, R)
AA(S, R) + AA(B, R)= 0.141
Purity of LO-SWNT = (0.066/0.141) 100% = 47%
0.00
0.05
0.10
0.15
0.20
Wavenumber (cm-1)
AA(B, R)
AA(S, R)
Absorb
ance
8000 9000 10000 11000 12000 130000.00
0.05
0.10
0.15
AA(B, LO)
AA(S, LO)
AA(S, LO)
AA(S, LO) + AA(B, LO)= 0.046
AA(S, R)
AA(S, R) + AA(B, R)= 0.096
Purity of LO-SWNT = (0.046/0.096) 100% = 48%
Method 2:
0.00
0.05
0.10
0.15
0.20
Wavenumber (cm-1)
AA(B, R)
AA(S, R)
Ab
so
rba
nce
8000 9000 10000 11000 12000 130000.00
0.05
0.10
0.15
AA(B, LO)
AA(S, LO)
Purity of carbonaceous materials (against R-SWNT)
Purity
(% of R-SWNT)
AP1-EA 101.9 1149.5 63
AP2-EA 50.2 962.2 37
AP3-EA 113.9 1162 70
AP4-EA 13.7 892.1 11
AP5-EA 60.4 1109.8 39
AP6-EA 43.2 960.1 32
P1-EA 158.5 971.6 116
P2-EA 252.3 1348.1 133
P3-EA 208.8 1304 113
AC 1 831.4 < 1
HC 138.5 2127.4 49~69
P-HC 165.2 2078.7 55~76
LO 62.6 1252.2 48~48
P-LO 85.4 803.8 92~110
Sample AA(S) AA(T)
63
37
70
11
3932
116
133
113
1
5966
47
101
0
20
40
60
80
100
120
140
Purity
(%
)
AP
1-E
AA
P2-E
A
AP
3-E
A
AP
4-E
A
AP
5-E
A
AP
6-E
A
P1-E
A
P2-E
A
P3-E
A
AC
HC
P
-HC
LO
P
-LO
8000 10000 12000 14000 16000
0.10
0.15
0.20
0.25
0.30
0.35
AA(I)
AA(N)
AA(S)
M11
S22
Absorb
ance
wavenumber (cm-1)
AA(T)=AA(S) + AA(N) + AA(I)
AA(T)
A(T) = A(S) + A(N) + A(I)
C(T) = C(NS) + C(I)
A(I) = (I) C(I) l
A(N) = (N) C(NS) l
A(S) = (S) C(NS) l
effective spectral absorbance: A =spectral width of cutoff
AA
The applicability of Beer’s law of carbonaceous materials
0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14
0
10
20
30
40
50
AP1-EA
AP2-EA
AP4-EA
P1-EA
P2-EA
Absorb
ance/C
oncentr
ation
Concentration (mg/mL)
0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.140
10
20
30
40
50
AP1-EA
AP2-EA
AP4-EA
P1-EA
P2-EA
AC
CB
MWNT
Absorb
ance/C
oncentr
ation
Concentration (mg/mL)
0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14
0
10
20
30
40
50
AP1-EA
AP2-EA
AP4-EA
P1-EA
P2-EA
AC
CB
MWNT
HC(S11
)
HC(S22
)
P-HC(S11
)
P-HC(S22
)
Absorb
ance/C
oncentr
ation
Concentration (mg/mL)
0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14
0
10
20
30
40
50
AP1-EA
AP2-EA
AP4-EA
P1-EA
P2-EA
AC
CB
MWNT
HC(S11
)
HC(S22
)
P-HC(S11
)
P-HC(S22
)
LO
P-LO
AP-C60
P-C60
Absorb
ance/C
oncentr
ation
Concentration (mg/mL)
(S) (T)
(Lmol-1cm-1) (Lmol-1cm-1)
AP1-EA 31 345
AP2-EA 15 289
AP3-EA 34 349
AP4-EA 4 268
AP5-EA 18 333
AP6-EA 13 288
P1-EA 48 292
P2-EA 76 405
P3-EA 63 391
AC 0 261
CB - 437
MWNT - 364
HC (S11) 118 382
HC (S22) 32 496
P-HC (S11) 129 386
P-HC (S22) 39 487
LO 15 301
P-LO 20 194
AP-C60 - 143
P-C60 - 2
Sample
Beer’s Law: A = C l
C = 0.01mg/mL 8.3 10-4 mol/LAP
1-E
A
AP
2-E
A
AP
3-E
A
AP
4-E
A
AP
5-E
A
AP
6-E
A
P1-E
A
P2-E
A
P3-E
A
AC
CB
MW
NT
HC
(S11)
HC
(S22)
P-H
C (S11)
P-H
C (S22)
LO
P-L
O
AP
-C60
P-C
60
345
289
349
268
333
288 292
405
391
261
437
364382
496
386
487
301
194
143
2
31
15 344 18 13
4876
63
0.1
118
32
129
39
15 20
0
50
100
150
200
250
300
350
400
450
500
(S)
(T)
A(T) = (I) C(I) + [(N) + (S)] C(NS)
A(T) = (I) C(T) + [(N) + (S) – (I)] (S) -1 A(S)
A(T)=A(S) + A(N) + A(I)
C(T)=C(NS) + C(I)
the intercept is (I) C(T)
the gradient is [(N) + (S) – (I)] (S) -1.
A(I) = (I) C(I)
A(N) = (N) C(NS)
A(S) = (S) C(NS)
0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07
0.22
0.24
0.26
0.28
0.30
0.32
0.34
A(T
)
A(S)
C = 0.01mg/mL 8.3 10-4 mol/L
(I) = 270 10 L mol-1 cm-1
Conclusion
Solution phase NIR is a powerful tool to assess
carbonaceous purity of SWNTs.
The Effective extinction coefficient of EA produced
SWNTs falls in the range of 268 ~ 391 L mol-1 cm-1 .
The effective extinction coefficient of carbonaceous
impurities in SWNTs is 270 10 L mol-1 cm-1 (calculation).
The relationship of extinction coefficient of carbonaceous
contents in EA-SWNTs is:
(N) (S) + (I) = (S) + 270 L mol-1 cm-1