Measurement Challenges for Carbon Nanotube Material
Edward Sosa1, Sivaram Arepalli1, Pasha Nikolaev1, Olga Gorelik1 and Leonard Yowell2
1 ERC Inc. / NASA - Johnson Space Center, Houston, TX 2 NASA - Johnson Space Center, Houston, TX
Abstract
The advances in large scale applications of carbon nanotubes demand a reliable supply of raw and processed materials. It is imperative to have a consistent quality control of these nanomaterials to distinguish material inconsistency from the modifications induced by processing of nanotubes for any application. NASA Johnson Space Center realized this need five years back and started a program to standardize the characterization methods. The JSC team conducted two workshops (2003 and 2005) in collaboration with NIST focusing on purity and dispersion measurement issues of carbon nanotubes [1]. In 2004, the NASA-JSC protocol was developed by combining analytical techniques of SEM, TEM, UV-VIS-NIR absorption, Raman, and TGA [2]. This protocol is routinely used by several researchers across the world as a first step in characterizing raw and purified carbon nanotubes. A suggested practice guide consisting of detailed chapters on TGA, Raman, electron microscopy and NIR absorption is in the final stages and is undergoing revisions with input from the nanotube community [3]. The possible addition of other techniques such as XPS, and ICP to the existing protocol will be presented. Recent activities at ANSI and ISO towards implementing these protocols as nanotube characterization standards will be discussed. Ref.: 1) http://mmptdpublic.jsc.nasa.gov/jscnano/
2) Arepalli S., Nikolaev P., Gorelik O., Hadjiev V. G., Holmes W. A., Files B. S., and Yowell L., “Protocol for the Characterization of Single-Wall Carbon Nanotube Material Quality”, Carbon, Vol. 42, pp. 1783-1791 (2004). 3) http://www.msel.nist.gov/Nanotube2/Carbon_Nanotubes_Guide.htm
https://ntrs.nasa.gov/search.jsp?R=20070001007 2018-07-26T00:28:34+00:00Z
Mea
sure
men
t C
ha
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no
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What are we buying?
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manufacturer in different batches?
•What are implications of nanotube purity in applications?
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electrical and thermal conductivity, surface area, sidewall
chemistry, dispersion properties, etc.?
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pu
rifie
d, 1
5min
So
nic
atio
n, 1
.595
% C
han
ge
Aft
er 1
Ho
ur
0
0.050.1
0.150.2
0.250.3
0.350.4 32
552
572
592
511
2513
25
Wav
elen
gth
(nm
)
Absorption
JSC
-A72
_1:
700-
1000
nm A
rea
49.6
5
JSC
-A72
_2:
700-
1000
nm A
rea
48.8
6
UV
-VIS
Dis
per
sio
n S
tud
y :
JSC
-A72
.2
JSC
Arc
un
pu
rifie
d-H
arve
stin
g S
tud
y, 1
20 m
in. S
on
icat
ion
, 0.6
665%
Ch
ang
e A
fter
1 H
ou
r
0
0.1
0.2
0.3
0.4
0.5
0.6 32
552
572
592
511
2513
25
Wav
ele
ng
th(n
m)
Absorption (arb. Units)
JSC
-A72
.2_1
: 70
0-10
00nm
Are
a 60
.55
JSC
-A72
.2_2
: 70
0-10
00nm
Are
a 60
.15
UV
-VIS
Dis
pers
ion
Stu
dy :
JSC
-A72
.4
JSC
Arc
unp
urifi
ed-H
arve
stin
g S
tudy
, 30
min
. Son
icat
ion,
0.1
114%
Cha
nge
Afte
r 1 H
our
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8 32
552
572
592
511
2513
25
Wav
elen
gth(
nm)
Absorption (arb. Units)
JSC
-A72
.4_1
: 700
-100
0nm
Are
a 73
.44
JSC
-A72
.4_2
: 700
-100
0nm
Are
a 73
.36
Ca
tho
de
Co
lla
rett
e
We
bs
Wa
ll D
ep
osit
Need
to
fo
cu
s i
n o
n t
hese r
eg
ion
s
Arc
Ma
teri
al
Va
ria
bil
ity
: C
on
clu
sio
ns
TG
A:
Lo
wer
oxid
ation tem
ps for
mate
rial fu
rther
from
ele
ctr
odes m
ore
lik
ely
due t
o s
om
e d
egre
e o
f over-
coating.
Lo
wer
meta
l conte
nt observ
ed in
vers
ely
to d
ista
nce fro
m e
lectr
odes.
Ram
an
:
D-b
an
d d
oes n
ot support
TG
A c
arb
on im
purity
specula
tion
.
RB
M s
ugg
ests
sm
alle
r dia
mete
rs m
ore
pre
vale
nt in
cath
ode m
ate
ria
ls.
G-b
and m
ay s
ho
w m
ore
meta
llic featu
res in c
ath
ode m
ate
ria
l, w
hile
more
SC
featu
res in w
all
dep
osit.
UV
-Vis
:
Su
ppre
ssed o
ptica
l fe
atu
res s
upport
over-
coating o
f tu
bes.
Str
onger
S22 tra
nsitio
n in a
gre
em
ent w
ith R
am
an r
esults.
HiP
co M
ate
ria
l V
ari
ab
ilit
y S
tud
y -
TG
A
Fro
nt
En
d C
olle
cti
on
-0.4
-0.2
0.0
0.2
0.4
0.6
Deriv. Weight (%/°C)
20
40
60
80
100
120
Weight (%)
0200
400
600
800
1000
Tem
pera
ture
(°C
)
Siz
e:
2.9
339 m
g
Ru
n #
1
357.9
5ºC
419.8
5ºC
554.7
6ºC
B-
28.3
5%
T
-30.6
1%
-0.2
0.0
0.2
0.4
0.6
Deriv. Weight (%/°C)
20
40
60
80
100
120
Weight (%)
0200
400
600
800
1000
Tem
pera
ture
(°C
)
Siz
e:
3.0
069 m
g
Ru
n #
2
364.3
0ºC
418.2
6ºC
551.5
8ºC
B-
30.3
8%
T
-31.1
7%
-0.2
0.0
0.2
0.4
0.6
Deriv. Weight (%/°C)
20
40
60
80
100
120
Weight (%)
0200
400
600
800
1000
Tem
pera
ture
(°C
)
Siz
e: 2.9
74
1 m
g
Ru
n #
3
B-
29.0
5%
T
-30.2
6%
361.1
3ºC
418.2
6ºC
554.7
6ºC
Ba
ck
En
d C
oll
ec
tio
n
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
Deriv. Weight (%/°C)
0
20
40
60
80
100
120
Weight (%)
0200
400
600
800
1000
Tem
pera
ture
(°C
)
Siz
e: 2.9
42
7 m
g
367.4
8ºC
B-
20.4
2%
T
-19.7
4%
389.7
0ºC
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
Deriv. Weight (%/°C)
0
20
40
60
80
100
120
Weight (%)
0200
400
600
800
1000
Tem
pera
ture
(°C
)
Siz
e: 2.9
695 m
g
367.4
8ºC
388.1
1ºC
B-
20.1
1%
T
-19.6
4%
-10123
Deriv. Weight (%/°C)
0
20
40
60
80
100
120
Weight (%)
0200
400
600
800
1000
Tem
pera
ture
(°C
)
Siz
e: 2.8
543 m
g
366.0
8ºC
389.9
3ºC
B-
21.6
5%
T
-19.0
5%
Re
su
lts:
1. B
oth
Ma
teri
als
sh
ow
go
od h
om
oge
ne
ity fro
m c
on
sis
tent T
GA
sp
ectr
a
2. B
ack e
nd
ma
teri
al d
isp
lays c
om
bu
stive
be
ha
vio
r
3
. B
ack e
nd
ma
teri
al h
as ~
33
% le
ss n
on
-ca
rbo
n im
pu
ritie
s
HiP
co M
ate
rial
Vari
ab
ilit
y S
tud
y:
UV
-Vis
-NIR
HiP
co
Va
ria
bilit
y S
tud
y -
Ba
ck
En
d M
ate
ria
l
0.1
5
0.2
5
0.3
5
0.4
5
0.5
5
0.6
5
0.7
5
30
05
00
70
09
00
11
00
13
00
15
00
Wav
ele
ng
th (
nm
)
Absorption
Perc
ent A
bsorp
tion C
hang
e: 18.3
5%
HiP
co
Va
ria
bilit
y S
tud
y -
Fro
nt
En
d M
ate
ria
l
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
300
500
700
900
1100
1300
1500
Wav
ele
ng
th (
nm
)
Absorption
Perc
ent A
bsorp
tion C
hang
e: 1.9
3%
SW
CN
T M
easu
rem
ent
Ch
all
enges
Cu
rren
t st
ate
of
reli
ab
ilit
y a
nd
un
cert
ain
ty
NA
SA
-JS
C p
roto
col
for
pu
rity
an
d d
isp
ersi
on
Stu
dy
of
fin
e va
ria
tio
ns
in h
arv
este
d m
ate
ria
l
-Lase
r, a
rc a
nd
CV
D p
rod
uct
ion
ch
am
ber
s
Ad
dit
ion
s to
NA
SA
-JS
C p
roto
col
-“N
on
-na
no
tub
e”ca
rbon
an
d n
an
od
isp
ersi
on
Na
no
tub
e ch
ara
cter
iza
tio
n s
tan
da
rds
Fu
ture
Wo
rk
8000
10000
12000
8000
10000
12000
8000
10000
12000
0.0
0.2
0.4
0.0
0.1
= 0
.095
A(T
,S1)
A(S
22,S
1)
S1
A(S
22,S
1)
(b)
A(T
,S1) S
WN
Ts:
67%
CA
RB
ON
AC
EO
US
IM
PU
RIT
IES
: 33%
Wavenum
ber
(cm
-1)
(c)
A(T
,S2)
SW
NT
s:
40%
CA
RB
ON
AC
EO
US
IM
PU
RIT
IES
: 60%
Wavenum
ber
(cm
-1)
= 0
.057
A(T
,S2)
A(S
22,S
2)
A(S
22,S
2)
S2
(a)
RE
FE
RE
NC
E (
R2)
A(T
,R2)
Absorbance
Wavenum
ber
(cm
-1)
= 0
.141
A(T
,R2)
A(S
22,R
2)
A(S
22,R
2)
R2
No
n-n
an
otu
be
Ca
rbo
n b
y N
IR A
bso
rpti
on
M.
E.
Itk
is,
et a
l. N
ano
Let
t, 3
, 3
09
(2
003
)
50
00
10
00
01
50
00
0.0
0
0.0
5
0.1
0
0.1
5
0.0
0.1
0.2
0.3
S22
S11
CA
RB
ON
BLA
CK
PU
RIF
IED
SW
NT
S
AN
NE
AL
ED
PU
RIF
IED
SW
NT
s
(a)
Absorbance
Wa
ve
nu
mb
ers
(cm
-1)
M11
AP
SW
NT
s
(b)
HiP
co
Vari
ab
ilit
y S
tud
y -
Back E
nd
Mate
rial
0.1
5
0.2
5
0.3
5
0.4
5
0.5
5
0.6
5
0.7
5 300
500
700
900
1100
1300
1500
Wa
ve
len
gth
(n
m)
Absorption
Pe
rce
nt
Ab
so
rptio
n C
ha
nge
: 1
8.3
5%
-101
M11
meta
llic
DO
S
energy (eV)
-101
sem
ico
nd
uctin
g
DO
S
S22
S11
energy (eV)
2000
1000
6
66
M 1
1
S 2
2S
11
Wav
elen
gth
(nm
)
How
do
We
Per
form
Ch
ara
cter
iza
tio
n?
Nan
osc
op
ic
•T
ran
smis
sion
Ele
ctro
n M
icro
scop
y
(TE
M)
•A
tom
ic F
orc
e
Mic
rosc
opy (
AF
M)
•S
cannin
g T
unnel
ing
Mic
rosc
opy (
ST
M)
Mic
rosc
op
ic
•S
can
nin
g E
lect
ron
M
icro
scop
y (
SE
M)
•E
ner
gy D
isp
ersi
ve
X-r
ay A
naly
sis
(ED
X)
•R
am
an
Sp
ectr
osc
op
y
•X
-ray
Photo
elec
tron
Spec
tro
scopy (
XP
S)
Macr
osc
op
ic
•T
her
mal
Gra
vim
etri
c A
naly
sis
(TG
A)
•U
V-V
isib
le-N
ear
Infr
are
d (
UV
-Vis
-N
IR)
Ab
sorp
tion
•N
IR F
luore
scen
ce
•In
duct
ivel
y C
ou
ple
d
Pla
sma
(IC
P)
•O
pti
cal
Mic
rosc
op
y
•D
ynam
ic L
ight
Sca
tter
ing (
DL
S)
•X
-ray
Dif
frac
tio
n
(XR
D),
SA
XS
, S
AN
S
•R
esis
tiv
ity
•S
urf
ace
Are
a(B
ET
)
•T
ensi
le S
tren
gth
•T
her
mal
Conduct
ivit
y
Pu
rity
an
dD
isp
ersi
on
Macr
od
isp
ersi
on
an
d N
an
od
isp
ersi
on
Op
tica
l D
isp
ersi
on
An
aly
sis
Pro
toco
l
Gu
idel
ines
for
a q
ua
nti
tati
ve
rep
rod
uci
ble
pro
toco
l:
•F
oll
ow
guid
elin
es f
or
UV
-Vis
pro
toco
l an
d e
stab
lish
dis
per
sio
n g
rad
e (A
, B
, o
r C
).
•O
nce
dis
per
sio
n g
rade
has
bee
n a
ssig
ned
, so
nic
ate
sam
ple
(0
.1 m
g/
mL
) fo
r 1
h.
•A
fter
1 h
of
sonic
atio
n, al
low
sam
ple
to
res
t at
ro
om
te
mp
erat
ure
fo
r 1
h.
•S
tir
sam
ple
tho
rou
ghly
an
d r
emo
ve
an a
liqu
ot
(17u
L)
•A
vo
lum
e o
f 17
uL
wa
s fo
und
to
be
idea
l fo
r fu
ll
cove
rag
e b
y a
sli
de
cove
r. T
his
volu
me
min
imiz
ed
the
form
ati
on
of
vacu
ole
s w
ith
out
exce
ss s
pil
lag
e o
uts
ide
22
mm
x 2
2m
m a
rea
.
•U
se t
he
Op
tica
l C
om
par
ito
r at
10
0x
mag
nif
icat
ion
eq
uip
ped
wit
h a
gri
d t
o c
ou
nt
the
par
ticl
e dis
trib
uti
ons
wit
hin
an a
rea.
•C
ou
nt
an a
rea
that
rep
rese
nts
th
e hig
hes
t co
nce
ntr
atio
n o
f p
arti
cles
in
th
e sa
mple
•U
se t
he
OD
A P
roto
col
Tab
le t
o d
eter
min
e th
e dis
per
sio
n g
rad
e.
Nik
on V
12A
Com
par
ator 0.0
2”
100X
Alc
ohol
CV
D
HiP
co
NIR
Flu
ore
scen
ce f
or
Na
no
dis
per
sio
n
Ch
irali
ty D
eter
min
ati
on
-101
sem
ico
nd
uctin
g
DO
S
S22
S11
energy (eV)
Po
ssib
le A
dd
itio
ns
to J
SC
Pro
toco
l
NIR
Ab
sorp
tion
fo
r P
uri
ty A
sses
smen
t
OD
A,
and
NIR
Flu
ore
scen
ce f
or
Dis
per
sion
AF
M f
or
Len
gth
s an
d D
iam
eter
s
E-B
eam
Dif
frac
tion
, S
TM
fo
r C
hir
alit
y
Ele
ctri
cal
Condu
ctiv
ity
Th
erm
al C
ondu
ctiv
ity
Mec
han
ical
Str
ength
Mea
sure
men
ts
TG
A-I
R/M
S f
or
Fun
ctio
nal
Gro
up
Ass
essm
ent
SW
CN
T M
easu
rem
ent
Ch
all
enges
Cu
rren
t st
ate
of
reli
ab
ilit
y a
nd
un
cert
ain
ty
NA
SA
-JS
C p
roto
col
for
pu
rity
an
d d
isp
ersi
on
Stu
dy
of
fin
e va
ria
tio
ns
in h
arv
este
d m
ate
ria
l
-Lase
r, a
rc a
nd
CV
D p
rod
uct
ion
ch
am
ber
s
Ad
dit
ion
s to
NA
SA
-JS
C p
roto
col
-“N
on
-na
no
tub
e”ca
rbon
an
d n
an
od
isp
ersi
on
Na
no
tub
e ch
ara
cter
iza
tio
n s
tan
da
rds
Fu
ture
Wo
rk
Na
no
tub
e ch
ara
cter
iza
tio
n s
tan
da
rds
NA
SA
-NIS
T C
oll
ab
ora
tio
n
--P
uri
ty a
nd
Dis
per
sion
Wo
rksh
op
s 20
03
an
d 2
00
5
--P
ract
ice
Gu
ides
on
web
pa
ge
htt
p:/
/ww
w.m
sel.
nis
t.go
v/N
an
otu
be2
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rbo
n_
Na
no
tub
es_
Gu
ide.
htm
NA
SA
-IE
EE
Co
lla
bora
tio
n
--D
evel
op
men
t o
f IE
EE
-P16
90
“M
eth
od
s fo
r th
e
Ch
arac
teri
zati
on
of
Car
bon
Nan
otu
bes
Use
d a
s A
ddit
ives
in
Bu
lk M
ater
ials
”
NA
SA
-AN
SI-
ISO
Co
lla
bora
tio
n u
nd
er I
SO
-TC
229
for
Na
no
tech
no
logy
--M
ajo
r P
layer
in
th
e U
S T
AG
fo
r W
G2
on
Ch
ara
cter
iza
tio
n
--R
esp
on
sib
le f
or
cha
ract
eriz
ati
on
sta
nd
ard
s o
f
SW
CN
Ts
SW
CN
T M
easu
rem
ent
Ch
all
enges
Cu
rren
t st
ate
of
reli
ab
ilit
y a
nd
un
cert
ain
ty
NA
SA
-JS
C p
roto
col
for
pu
rity
an
d d
isp
ersi
on
Stu
dy
of
fin
e va
ria
tio
ns
in h
arv
este
d m
ate
ria
l
-Lase
r, a
rc a
nd
CV
D p
rod
uct
ion
ch
am
ber
s
Ad
dit
ion
s to
NA
SA
-JS
C p
roto
col
-“N
on
-na
no
tub
e”ca
rbon
an
d n
an
od
isp
ersi
on
Na
no
tub
e ch
ara
cter
iza
tio
n s
tan
da
rds
Fu
ture
Wo
rk
Fu
ture
Work
•U
pd
ate
ch
ara
cter
iza
tion
pro
toco
l fo
r p
uri
ty a
nd
dis
per
sio
n o
f S
WC
NT
s
•Id
enti
fy a
nd
dev
elo
p m
easu
rem
ent
sta
nd
ard
s fo
r th
is
cha
ract
eriz
ati
on
pro
toco
l
SE
M,
TE
M, T
GA
, R
am
an
, U
V-V
IS-N
IR
Ab
sorp
tion
, O
pti
cal
Dis
per
sio
n A
na
lysi
s, N
IR
Flu
ore
scen
ce
Dr.
Ram
All
ada
Dr.
Siv
aram
Are
pal
li
Dr.
Bra
d F
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Dr.
Olg
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Dr.
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Mr.
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Molo
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Mr.
Wil
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Holm
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Mr.
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Ms.
Bea
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htt
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c.nas
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