raman effect in carbon nanotubes filled with nanowires

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RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH NANOWIRES E. Belandria E. Flahaut J. González

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RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH NANOWIRES. E. Belandria E. Flahaut J. González. Synthesis. Double-wall carbon nanotubes (DWCNT) were prepared by CVD. - PowerPoint PPT Presentation

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Page 1: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH NANOWIRES

E. Belandria

E. Flahaut

J. González

Page 2: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES
Page 3: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Synthesis Double-wall carbon nanotubes (DWCNT)

were prepared by CVD. HRTEM images reveals that samples

produced contain approximately 77% of DWCNTs, with a small admixture of about 18% singlewall carbon nanotubes (SWCNTs), and roughly 5% triple-wall carbon nanotubes.

Page 4: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

RAMAN RESONANTE

Lii EE

100 150 200 250 300 3500,0

0,5

1,0

1,5

2,0

2,5

3,0EM

11ES

33

ES22

Láser 1.916 eV

Láser 2.182 eV

Sepa

raci

ón e

n En

ergí

a (e

V)

RBM (cm-1)

Láser 2.410 eV

ES11

Page 5: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

50 100 150 200 250 300 350

Inte

nsid

ad(U

.A.)

Número de Onda (cm-1)

Energía Láser: 2.410 eV

100 150 200 250 300 350

Energía Láser: 2.182 eV

Inte

sida

d (U

.A.)

Número de onda (cm-1)

100 150 200 250 300 350 400

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

Energía Láser: 1.916 eV

100 150 200 250 300 350

2,25

2,50

Sepa

raci

ón e

n En

ergí

a (e

V)

RBM (cm-1)

(c)

100 150 200 250 300 350

1,75

2,00

2,25

2,50

Sepa

raci

ón e

n En

ergí

a (e

V)

RBM (cm-1)

(b)

100 150 200 250 300 3501,5

2,0

2,5

Sepa

raci

ón e

n En

ergí

a (e

V)

RBM (cm-1)

(a)

Page 6: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Chirality

Diameter (nm)

RBMDFT (cm-1)

Laser Line 1,916eV Laser Line 2,182eV Laser Line 2,410eV

Inner /

Outer

RBM exp(cm-1)

FWHM (cm-1)

Intensity (%)

RBM exp(cm-1)

FWHM (cm-1)

Intensity (%)

RBM exp(cm-1)

FWHM (cm-1)

Intensity (%)

Sem (9,1) 0,749 325,08 341 3.64 1 InnerSem (10,0) 0,785 310,97 304 21.33 12 310 5.33 6 InnerSem (8,4) 0,83 294,83 292 3.00 39 291 3.77 12 InnerSem (11,0) 0,862 284,32 286 5.40 62 InnerSem (7,6) 0,883 277,93 280 3.49 83 278 15.07 22 InnerSem (10,3) 0,923 266,41 264 6.83 36 InnerMet (12,0) 0,939 262,03 266 7.15 100 InnerSem (9,5) 0,962 256,27 257 4.22 39 257 1.86 13 255 4.99 52 InnerSem (12,1) 0,980 251,64 254 4.66 50 247 9.92 86 InnerMet (9,6) 1,023 241,80 240 9.16 62 InnerMet (13,1) 1,058 234,26 233 6.15 100 SWMet (12,3) 1,075 230,77 SWMet (11,5) 1,108 224,25 222 7.63 78 223 17.93 37 InnerMet (10,7) 1,156 215,48 216 9.86 63 InnerMet (12,6) 1,240 201,91 200 10.68 19 201 2.64 19 InnerSem (16,3) 1,381 182,72 184 5.47 8 SWSem(11,10) 1,420 178,09 179 81.23 7 OuterSem (14,7) 1,445 175,20 174 15.06 31 174 16.54 34 OuterSem(13,11) 1,623 157,55 158 15.69 100 OuterSem (16,8) 1,651 155,14 155 5.58 58 153 19.48 10 OuterSem(15,10) 1,700 151,08 151 3.84 41 150 28.34 31 OuterSem (23,3) 1,921 135,32 135 21 23 OuterMet (22,22) 2,967 92,52 92 1.65 37 SW

Page 7: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Nan

otub

os R

elle

nos

con

Telu

ro

100 150 200 250 300 350

Te

NT (15,10)

NA

NT (14,7)

NT (16,3)

NT (12,6)

NT (10,7)

NT (12,3) NT (12,0)

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

NT (10,0)

150

100

50

M Γ A

1,75 2,00 2,25 2,50 2,75 3,00

1320

1380

Num

ero

de O

nda

(cm

-1)

Energía de Excitación (eV)

1218 + 52 * EEXC(eV)

Te@CNT

1300 1400 1500 1600 1700

Emptys1595

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

Te1581

Eg2.2 eV

Modos Tangenciales

Dispersión Banda D

Page 8: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Nan

otub

os R

elle

nos

con

Sele

nio

150 200 250 300

NT (15,0)

NA

NT (16,3)

NT (10,7)

NT (12,6)

NA

NT (9,6)

NT (9,5)

NT (10,3)

NT (7,6)

NT (11,0)

NT (10,0)

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

1,8 2,0 2,2 2,4 2,6 2,8

1320

1380

Num

ero

de O

nda

(cm

-1)

Energía de Excitación (eV)

1218 + 52 * EEXC(eV)

Se@CNT

50 100 150 200 250 300 350

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

Se@DWCNT

Se Amorfo

Se Romboedral

Se Monoclinico

Se Trigonal

1400 1450 1500 1550 1600 1650 1700

Empty1595

Se@1589

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

Eg2.3 eV

Modos Tangenciales

Dispersión Banda D

Page 9: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Nan

otub

os R

elle

nos

con

PbTe

100 150 200 250 300

NT(9,6)NT(10,0)NT(11,0)

NT(9,5)

NT(10,3)

NT(11,5)

NT(10,7)

NT(12,6)

PbTeNT(16,3)

PbTeNT(13,11)

NT(15,10)NT (23,3)

PbTe

NA

Inte

nsid

ad (U

.A.)

Número de Onda(cm-1)

NA

ω (cm-1) Ancho Asignación 117 13 NA 124 2 NA 129 7 PbTe 137 11 NT(23,3) 152 16 NT(15,10) 159 3 NT(13,11) 165 14 PbTe 184 10 NT(16,3) 197 15 PbTe 203 6 NT(12,6) 210 8 NT(10,7) 225 6 NT(11,5) 248 9 NT(9,5) 259 14 NT(9,6) 268 5 NT(10,3) 285 6 NT(11,0) 307 9 NT(10,0)

1,8 2,0 2,2 2,4 2,6 2,8

1300

1320

1340

1360

1380

Num

ero

de O

nda

(cm

-1)

Energía de Excitación (eV)

1218 + 52 * EEXC(eV)

PbTe@CNT

1300 1350 1400 1450 1500 1550 1600 1650 1700

Empty1595

PbTe@1578

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

Eg2.15 eV

Modos Tangenciales

Dispersión Banda D

Page 10: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Nan

otub

os R

elle

nos

con

HgT

e

100 150 200 250 300 350

NT(9,5)

NT(10,3)

NT(10,0)

NT(9,6)NT(11,5)

NT(10,7)

NT(12,6)

NA

NT(16,3)NT(11,0)

NT(14,7)

NA

HgTeNT(15,10)

NT(23,3)NA

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

HgTe

1,8 2,0 2,2 2,4 2,6 2,8

1300

1320

1340

1360

1380

Num

ero

de O

nda

(cm

-1)

Energía de Excitación (eV)

1218 + 52 * EEXC(eV)

HgTe@CNT

1300 1400 1500 1600 1700

Empty1595HgTe@

1576

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

Eg2.12 eV

Modos Tangenciales

Dispersión Banda D

Page 11: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Nan

otub

os R

elle

nos

con

CdSe

100 150 200 250 300

CdSe@DWCNT DWCNT

Inte

nsid

ad (A

.U)

Número de Onda (cm-1)

LO CdSe

TO CdSe

SO CdSeInner Tubes

OuterTubes

100 150 200 250

NT(8,6)

NT(10,3)NT(13,0)NT(11,7)

NT(12,8)

NT(11,10)

CdSe SOCdSe

NT(16,9)NT(19,9)

NA

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

NA

CdSe SO

CdSe

1,8 2,0 2,2 2,4 2,6 2,8

1300

1320

1340

1360

1380

Num

ero

de O

nda

(cm

-1)

Energía de Excitación (eV)

1218 + 52 * EEXC(eV)

CdSe@CNT

1300 1350 1400 1450 1500 1550 1600 1650

Empty1595CdSe@

1593

Inte

nsid

ad (U

.A.)

Número de Onda (cm-1)

Modos Tangenciales

Dispersión Banda D

D. Nesheva, H. Hofmeister, Z. Levi and Z. Aneva. Vacuum 65 (2002) 109–113

Page 12: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

RBM & CdSe Modes

100 150 200 250 300

Empty Filled

Inte

nsity

(A.U

)

Wavenumber (cm-1)

LO CdSe

TO CdSe

SO CdSeInner Tubes

OuterTubes

Page 13: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Assignment RBMs ModesInner Outer

ωRBM (n,m) dDFT ωRBM (n,m) dDFT

183,86 (12,8) 1,372 127,42 (18, 12) 2,054203,48 (10,8) 1,230 135,38 (16, 12) 1,920245,48 (11,3) 1,007 151,77 (21, 1) 1,691254,42 (11,1) 0,969 155,47 (18, 4) 1,647264,48 (10,3) 0,930 158,45 (20, 1) 1,613270,00 (9,5) 0,910 160,01 (18, 5) 1,596

ωRBM (n,m) dDFT

164,44 (16,6) 1,549SWCNT

Page 14: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Assignment CdSe Modes

168.95 TO CdSe173.51 SO CdSe180.31 SO CdSe187.77 SO CdSe199.15 Confined LO CdSe

Page 15: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

CdSe LO Confined

194 196 198 200 202 204 206 208 210 212

196 200 204 208 212Inte

nsity

(A.U

.)

Wavenumber (cm-1)

CdSeLO Confinedd=8,7865 A

CNT

Page 16: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

InnerωRBM (n,m) dDFT

183,86 (12,8) 1,372

203,48 (10,8) 1,230245,48 (11,3) 1,007254,42 (11,1) 0,969264,48 (10,3) 0,930270,00 (9,5) 0,910

Cluster de Cd6Se6 con estructura wurzita y aproximadamente de diámetro 0.8 nm

Page 17: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Surface Phonons in Nanowires

xfm

TOLOTOSO

2222

1,0;

)()()()(

)(

mrqx

xIxKxKxI

xfmxm

mxm

lqrqx

xIxKxKxIxf

210

10

)()()()()(

εw

εm

Para m=0

Page 18: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES
Page 19: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

a

b

c

||

r

z

rz ˆˆˆ||)(

Page 20: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

Para radiación con energía de 2.41 eV i05960870.730666411.5 8319.8

lqrqx

xIxKxKxIxf

210

10 ;)()()()()(

xfTOLO

TOSO

22

22

SO f(x) x q x10-9 l

173.51 8.1739 0.4636 1.0553 5.95 nm180.31 3.0218 1.0569 2.4057 2.61 nm187.77 1.4487 2.8922 6.5833 0.95 nm

A39325.41682139.8 11 rcmcm TOLO

Page 21: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

1,5 2,0 2,5 3,0 3,5 4,0 4,5

1280

1300

1320

1340

1360

1380

1400

1420

1440

1460

1480

Núm

ero

de O

nda

(cm

-1)

Energía de Excitación (eV)

Vacios PbI

2

Fe CdSe HgTe PbTe B Te

1450 1500 1550 1600 1650

Inte

nsid

ad (U

.A)

Número de onda (cm-1)

DWCNTCdSe@DWCNT

Te@DWCNTSe@DWCNT

PbI2@DWCNT

PbTe@DWCNT

HgTe@DWCNT

Vacios CdSe Se PbI2 Te PbTe HgTe

157415761578158015821584158615881590159215941596

Num

ero

de O

nda

(cm

)-1

Material de Relleno

A L

LAnportadoresN

Se Te PbTe HgTe

Page 22: RAMAN EFFECT IN CARBON NANOTUBES FILLED WITH  NANOWIRES

ConclusionsIn conclusion, we have carried out a detailed Raman measurements of DWCNTs filled with nanowires of Se, Te, HgTe, PbTe, CdSe and PbI2, the HRTEM measurements indicated that all nanowires is contained inside the inner carbon nanotube. The redshift of the G-band can be used as a measure of the filling factor of the nanotubes, as long as the excitation energy exceeds the gap of the nanowires contained within.