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Location of Novosibirsk in Russia
Nikolaev Institute of Inorganic
Chemistry Siberian Branch of RAS
Laboratory of Physics
Chemistry of Nanomaterials
Main topics:
1. Synthesis of CNTs
(CCVD, arc discharge);
2. PE CVD diamond
growth;
3. Chemical modification of
carbon;
4. Electronic structure (Xray spectroscopy,
quantum chemistry);
5. Properties – field
emission, gas sensor,
electrochemistry
Synthesis and study of carbon nanomaterials
Arrays of aligned
carbon and CNx
nanotubes
Fullerene
C60 and C70
Single- and multiwall carbon nanotubes
Diamond films
and nanodiamond
Graphene
and modification
4
CVD synthesis of carbon nanotubes
1. Катализатор на носителе.
2. Аэрозольный CVD синтез.
1) Регулирование морфологии наноструктур
2) Влияние на состав и допирование
наноструктур
3) Синтез упорядоченных структур в
заданных областях поверхности.
New catalysts for CNT synthesis
Aerosol-assisted CVD for synthesis
CNT arrays
Application CNT in MEMS
Formation of free standing CNT films
1 мм
200 мкм
Investigation of nitrogen doped CNT
Aerosol assisted CVD produced CNx CNT
from acetonitrile and acetonitrile/toluene
mixture
Chemical forms of nitrogen in CNx CNT
«Pyridinic»
«Graphitic»
B
4,5
Интенсивность, отн. ед.
4,0
A
N 1s
C
N2
CH3CN
0%
25%
50%
75%
100%
N общее
0.3
1.23
1.71
2.36
2.89
-
0.36
0.67
0.66
0.95
N графит. 0.3
0.74
0.92
1.35
1.22
N2
0.13
0.12
0.35
0.72
100% N пирид.
3,5
3,0
2,5
75%
2,0
50%
1,5
1,0
0,5
0,0
-0,5
-1,0
390
395
400
405
Энергия связи, эВ
-
25% 1) Добавка 25% CH3CN увеличивает
содержание азота на 0.5 атомных %
0% 2) При использовании в качестве газаносителя N2, часть азота
встраивается в стенки нанотруб
410
3) Формирование «графитового» азота
более выгодно
Chemical forms of nitrogen in CNx CNT
Double layered supercapacitors
Зависимость удельной емкости от
температуры прогрева наноалмазов
Зависимость удельной емкости
от скорости развертки
Получены емкости более 500 Ф/г
Influence of nitrogen concentration on
lithium electrochemical capacity
Увеличение концентрации азота
увеличивает электрохимическую
емкость Li-ионного аккумулятора
AX5250 Seki Technotron CVD System
Синтез алмазных пленок 200 мкм на полированном кремнии 1,5 мм диам. 50 мм
Т= 900 – 950 С; 4500 Вт
Водород-Ацетон 500/16
B
400000
Continued S04
T=840 - 880
p=119.2 - 119.4
W=2990
H2/CH4/O2 = 502 / 18.1 / 2.1
350000
Y Axis Title
300000
250000
200000
150000
100000
50000
0
1000
1200
1400
1600
1800
X Axis Title
2000
2200
2400
Synthesis CNT/Diamond composites
W ~ 5 kW
W ~ 600 W
CNT arrays was treated by
hydrogen/acetone plasma with
different power.
Diamond microcrystals on CNT surface
3,0x10-7
600 µ
2,5x10-7
1000 µ
Etching of CNT tips
under
microwave
PE CVD process.
I, A
2,0x10-7
1,5x10-7
800 µ
400 µ
1,0x10-7
5,0x10-8
0,0
0
1
2
3
4
5
E, V/µ
The current-voltage characteristics of the sample
and the glow of diamonds
Strategies for graphene layers perforation
Hydrogen flow etching
800°C
ACSNano 6, 126 (2012)
KOH activation (thermal or microwave-assistent)
800°C
NanoLett 12, 1806 (2012)
Science 332, 1537 (2011)
Steaming etching
200nm
JACS 133, 15264 (2011)
Perforation of graphite in hot mineral
acid
graphite oxide
product
Treatment in hot acid
H2SO4, boiling temperature 280°C
H3PO4, boiling temperature 210°C
Graphite oxide
280°C,
1 hour
Formation of holes with a
characteristic size of 2 nm
concentrated
H2SO4
TEM image of perforated graphite after
anneling
Titan G2 60-300
Cs- correction
Graphene
New carbon material with unique
electronic, optical and mechanical
properties
Chemical modification, what gives ?!
Negative:
•Destruction of perfect system from carrier charges in graphene layer
Positive:
•Control of atomic charge state
•Gap variation
•Localization effects of 2D electronic states
Fluorinated graphite CF, C2F
1) High-temperature
fluorination (F2, T ~ 400°C)
1. O.Ruff, D.Bretschneider, F.Elert, Z. Anorg. Allg.
Chem., 217 (1934)
2. L.B. Ebert, J.L. Brauman, R.A. Huggins JACS, v.96,
25, (1974) 7841
3. V.K. Mahajan, R.P. Badachhape, J.L. Margrave,
Inorg. Nucl. Chem. Letters, 10 (1974) 1103
4. P. Kamarchik, J. Margrave “Poly(carbon
monofluoride): a solid, layered fluorocarbon” Accounts
of Chemical Research, v.11, (1978) 296-300
5. Y.Kita, N.Watanabe, Y.Fujii, JACS, 101, 14 (1979)
3832
2) Room temperature fluorination (BrF3)
1.
Stein L. // J. Amer. Chem. Soc. 1959. v. 81. № 6. P. 1273.
2.
Юданов Н.Ф., Чернявский Л.И. // Журн. структур.
химии. 1987. Т. 28. № 4. С. 86
Electronic and spatial structure of (CF)n
XPS of CF
Cluster C96F120
0
0
0
F 1s
side view
At%
52.14
47.05
0.82
7000
C 1s spectrum
289,1 eV
6000
Intensity, cps
5000
4000
3000
2000
1000
0
275
280
285
290
Binding energy, eV
295
300
top view
Calculation of X-ray emission spectra of (CF)n
Photon energy (eV)
272
X-ray emission
spectra
274
276
278
280
282
Intensity (a.u.)
CKα
672
674
284
FKα
676
678
C2p
680
682
F2p
Calculation of
partial states
DFT
B3LYP/6-31G
-20
286
-15
E (eV)
-10
684
Calculation of CK edge absorption spectra of (CF)n
Photon energy, eV
285
290
CK -edge
295
300
C
B
experiment
Cluster C95F120N+
Intensity, arb.unit.
A
π* (C-C)
C2p DOS
-8
-6
-4
-2
0
2
4
6
8
Z+1 approximation
390
395
400
Calculated energy, eV
405
I отн.
Fluorinated graphite C2F
2 mm
001
002
003
Change of layers packing from fresh to
dry C2F with o-ksilol.
001'
002'
002''
5
10
003''
15
20
2Θο
a)
«Wet» С2F;
b)
Drying 1 hour;
c)
Drying 24 hours
Structure of С2F
Optical microscopy and AFM study
C1s spectra of pristine and fluorinated
graphite samples
A (C*-CF)
25000
B (C*F)
20000
15000
10000
E (C*)
C (C*F2) D (C*F3)
5000
2000
1000
0
C 1s
At%
65.41
3.33
29.06
2.20
F 1s
Pos.
287.50
532.50
687.00
69.50
Intensity (arb. units)
C1s
• Два состояния атомов углерода
284
286
• Атомы фтора ковалентно связаны с атомами углерода
288
290
292
294
296
Binding energy (eV)
Possible fluorine pattern in C2F layer
30
NMR study of High T produced С2F
13C
MAS NMR
Giraudet et al. J. Phys. Chem. B 111(51)
(2007) 14143-14151
(a)
C-F
Cgraphitic
Csp3
C...F
200
150
100
50
0
-50
13
δ\ C /TMS (ppm)
(C2F)n
type
N. Watanabe model
NMR measurements of C2F(C7H16)
C----F
α-CH2
C-F β-CH
CF2
2
γ-CH2 CH3
•Determination of composition
13C
MAS NMR (10 kHz)
CF0.40(C7H16)0.04
Y. Sato et al. /
Carbon 42 (2004) 3243
•«Semi-covalent» - conjugation of F and C π systems
32
Experimental X-ray absorption spectra
measured near CK- and FK-edge of (C2F)n
A(π∗-C)
Intensity (rel. units)
B (σ*-CF) C
285
D
290
E
295
F
CK-edge
CK-edge
20o
90o
B' (σ*-FC)
A'(π∗-C)
300
FK-edge
20o
685
690
695
Photon energy (eV)
Эксперимент
C'
700
285
290
FK-edge
90o
F'
295
300
695
700
D' E'
685
690
Photon energy (eV)
Z+1 approach, B3LYP(6-31G) level
CK spectra of models
with contributions of C*CF and C-C*F
Experimental and
theoretical partial π* C
and σ* C-F density
Photon energy (eV)
285
290
295
300
305
2.0
20o
C
A
B
A
CK-edge absorption
1.5
C
experiment
B
1.0
D
E
armchair chain
Intensity (rel. units)
Intensity (a.u.)
zigzag chain
0.5
90o
0.0
290
C'
300
D'
E'
0.5
A' B'
double bonds
270
280
290
Calculated energy (eV)
0.0
280
290
300
Photon energy (eV)
310
Angle-depended X-ray
absorption spectra
σ*
CK-edge
π*
FK -edge σ *
Κ
90O
90o
90o
σC-F*
80O
80o
80o
50o
60O
50O
40O
70o
Intensity (arb. units)
60o
Intensity (arb. units)
Intensity (arb. units)
70o
70O
60o
50o
40o
40o
30O
30o
20O
20o
30o
20o
285
290
295
300
305
310
Photon energy (eV)
315
320
325
385
390
395
400
Energy (eV)
CK-edge absorption and calculated zig-zag model spectra
405
410
415
685
690
695
700
Photon energy (eV)
FK-edge absorption spectra
Absorption and luminescence of C2F
A. Gruneis measurements
C2F intercalated Br2
Optic micrograph of С2F
Br2
intercalated CCl4
Absorption (a.u.)
0,9
C2F(BrF3)
0,6
C2F(CCl4)
0,3
0,0
2
4
Photon energy (eV)
Blue C2F•BrF3
Absorption spectra of C2F•BrF3
C2F•CCl4
6
Luminescent
spectra of C2F•Br2
Forming of carbon layer on C2F surface
1. Physical way:
2. Chemical way:
Reduction of С2F surface under
irradiation by electrons
25
Глубина
проникновения
электронов в
C2F (МонтеКарло)
20
н
м,
Г
л
у
б
и
н
а
15
10
5
0
0
200
400
Эн
е
р
г
и
я
600
800
Program «Casino»
1000
Angle dependence of C 1s spectra
С
С-F
75o
Ин
т
е
н
с
и
в
н
о
с
т
ь
60o
C2F
45o
Model: substrate/film
Thickness of carbon layer
2 nm, [C]- 85 %
0o
с /и
мп
,
θ
294
292
290
288
Эн
е
р
г
и
я
286
284
Irradiated С2F(HOPG)
282
280
X-ray absorption spectra of fluorinated
graphite after irradiation (Auger electron yield)
1,0
0,8
CK- край
π∗
σ∗
0,6
0,4
HOPG
1,0
FK- край
0,0
1,0
0,8
0,6
σ∗
Intensity (rel. units)
Intensity (rel. units)
0,2
π∗
0,4
C2F HOPG
0,8
0,6
HOPG C2F,
200 eV, 10 min
500 eV, 10 min
0,4
0,2
0,2
0,0
0,8
0,6
0,0
σ∗
π∗
680
690
695
700
705
Photon energy (eV)
C2F HOPG
500 eV, 10 min
0,4
0,2
Reduction of carbon layer after
irradiation by electrons
0,0
280
685
285
290
295
Photon energy (eV)
300
40
40
Reduction of C2F surface by hydrazine and
water vapors
5
4000
V(t) = V1exp(- t/τ1)+ V2exp(-t/τ2)
τ1 = 2 sec, τ2 = 9 sec, τ3 = 28 sec
3000
2000
1000
N2H4
60
80
100
120
140
3
H2O
2
160
reduction time, sec
Схема контроля
восстановления
τ1 = 30 sec
τ2 = 2400 sec
4
R (GOm)
Resistance, MΩ
V(t) = V1exp(- t/τ1)+ V2exp(-t/τ2)+V3exp(-t/τ3)
180
200
2
4
6
T (min)
микротрещины
8
10
STM image of the surface of C2F sample
after long time storage
STM measurement
Raman spectra of C2F samples
Intensity, a.u.
G
3
D
2
1
1200
The surface has graphite-like
structure
Z. Osváth, L.P. Biro (2009)
1300
1400 1500 1600
Raman shift, cm-1
1700
1800
1 – fresh sample of fluorinated graphite
2 – stored in ambient conditions
3 – treated with water vapor
XPS spectra of treated fluorinated graphite with
different energy of exitation
C-C
C1s spectra of fluorinated
graphite:
C-F
1486.7 eV
after water vapor
A
B
treated by water vapor;
Intensity, a.u.
1486.7 eV
850 eV
680 eV
350 eV
315 eV
290
289
288
287
286
285
Binding energy, eV
284
283
282
stored in ambient conditions
Moving of fluorine atoms on the reduced
graphite fluoride surface
removing of
upper fluorine
atoms
relaxation of
the fragment
Initial fragment with zigzag chains
jumping of fluorine atoms
side view of the reduced surface
Gas - sensor properties carbon film on C2F
Set-up for sensor
measurements
25
NH3
NH3
air
NH3
air
Resistance, kΩ
24
23
22
21
20
0
6
12
18
24
Time, min
air
air
NO2
air
NO2
Eabs~200 meV
3.35 Å
Resistance, GΩ
100
10
3
6,8 ppm
4
5
6
7
8
9
Time, min
32,9 ppm
0,0592
0,0590
0,0588
He NH3 He NH3 He
NH3 He
NH3 He
He
0,0586
R, MΩ
0,0584
0,0582
0,0580
0,0578
0,0576
0,0574
0,0572
4
6
8
10
12
14
16
Time, min
18
20
22
24
26
Electronic structure of graphite
10
Interaction of NO2 molecule with
the reduced graphite fluoride surface
B3LYP, 6-31G**
No nitrogen on
the sensor surface
XPS
1
Intensity, cps
80000
2
F1s
60000
C1s
40000
20000
O1s
0
C-N distance is 2.89 Å
The charge of NO2 is -0.171 e
Eads = -0.107 eV
Eads = Ecomplex-Esheet-Emolecule
0
200
400
600
800
Binding energy, eV
weak interaction of NO2 with
the reduced C2F surface
46
NO2 accepts electrons
1000
TEM picture of fluorinated sample
• fluorinated plate
• well graphitized inner
shells of MWNT
• fluorinated surface
layers of MWNT
Character of C-F bonding in
the fluorinated material
C 1s spectrum
IR absorption spectrum
INTENSITY (a.u.)
Absorption (rel. units)
a b c
a
b
800
280
285
290
Binding energy (eV)
295
1000
1200
cm-1
pristine MWNT-based material
graphite fluoride C2F
fluorinated MWNT-based material
1400
1600
Degradation of MWNT with
fluorination
12
nm
a
Possible structure MWNT
synthesized in arc-discharge
Fluorinated SWNT
SWNT
Intensity (rel. units)
5
F-SWNT
XRD pattern
0
4
HRTEM picture of F-SWNT
5
6
7
2θ
disruption of SWNT rope
Conductivity of SWNT
2
1
0
l σ
c
-2
3
-4
-6
-8
-10
-12
2
-14
0
100
200
T (K)
pristine SWNT-based material
fluorinated material
defluorinated material
300
Fluorination of DWNT
Synthetic techniques:
(1) F2 flow (with HF traces)
at 200 ºC
(2) gaseous mixture of BrF3
and Br2 at room
temperature
(3) CF4 plasma with 15 Watt
power and 13.56 MHz
Pristine
BrF3
CF4 plasma
F2
Raman spectra DWNT measured with 488 nm exitation,
G
D
Intensity (arb. units)
CF4 plasma
fluorinated
CF4 plasma
fluorinated
Intensity (arb. units)
RBM
BrF3 fluorinated
F2 fluorinated
G
D
pristine DWNTs
1400
1600
Raman shift (cm-1)
1800
IR spectra
BrF3 fluorinated
outer shells
F2fluorinated
inner shells
Intensity (arb. units)
C-F
C=C
4
3
2
1
pristine DWNTs
100
200
300
Raman shift (cm-1)
400
750
1000
1250
1500
-1
Wavenumbers (cm )
1750
2000
Photoelectron spectroscopy study
of FDWNT
282
C 1s
284
286
288
290
292
C
C-F
F2
Intensity (arb. units)
C-CF
F_CNT
Total
composition
Surface
compositio
n
F2
CF0.33
CF0.53
BrF3
CF0.22
CF0.34
CF4
CF0.17
CF0.26
BrF3
СF4
ДУНТ
282
284
286
288
290
Binding energy (eV)
292
Composition of the sample produced
was determined from XPS data
X-ray absorption spectra of FDWNT
С 1sMO* (C 2p AO)
σ∗
C K-edge
π∗ C-F
F 1sMO* (F 2p AO)
F2
B
σ∗
π∗
F2
π∗
σ∗
C-F
CF4
π∗
σ∗
C-F
Intensity (arb. units)
BrF3
Intensity (arb. units)
F K-край
A
C-F
BrF3
CF4
DWNT
690
280
C σ∗
290
300
Photon energy (eV)
310
695
700
705
Photon energy (eV)
710
Decomposition of C1s-spectra of the fluorinated
DWNT sample heated at different temperatures
80 b
A
Intensity (arb.units)
B
190°С
C
2700C
1900C
20°С
70
Spectral component ratio
270°С
60
50
40
B
30
20
200C
A
C
10
0
50 100 150 200 250 300
282 284 286 288 290 292
Binding energy (eV)
Temperature, 0C
Thank you for your attention!
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