S1

Supplementary Material (ESI) for Nanoscale This journal is (c) The Royal Society of Chemistry 2011

Supplementary data

A General Procedure to Synthesize Highly Crystalline Metal Oxide and

Mixed Oxide Nanocrystals in Aqueous Medium and Photocatalytic

Activity of Metal/Oxide Nanohybrids

Thanh-Dinh Nguyen, Cao-Thang Dinh, and Trong-On Do*

Department of Chemical Engineering, Laval University, Quebec G1K 7P4 Canada

To whom correspondence should be addressed. E-mail: Trong-On.Do@gch.ulaval.ca

SUBMITTED TO Nanoscale - January 2011

S2

Wavelength (nm)

400 450 500 550 600

Inte

nsity (

a.u

.)

Wavelength (nm)

300 350 400 450 500

Inte

nsity (

a.u

.)

283

Emission

Excitation

(a) (b)

434

449

486

529 560

Figure S1. (a) UV-visible adsorption and (b) photoluminescence (PL) spectra of 5.0 mol%

Eu3+

:NdVO4 nanorods dispersion in water.

S3

Figure S2. TEM images of typical La2(MoO4)3 nanocrystals synthesized hydrothermally at 180 oC for

the different reaction times: (a) 2 h, (b) 6 h, and (c) 20 h. (d) Schematic illustration of the proposed

growth mechanism of the RE2(MoO4)3 nanosheets.

S4

Binding Energy (eV)

0 200 400 600 800 1000

Inte

nsity (

CP

S)

Binding Energy (eV)

390 393 396 399 402

Inte

nsity (

CP

S)

Binding Energy (eV)

284 286 288 290

Inte

nsity (

CP

S)

(a)

(c) (d)

Binding Energy (eV)

529 530 531 532 533In

ten

sity (

CP

S)

(b) O 1s

C 1sN 1s

O 1

s

Mo

3d

N 1

s

C 1

s

La

3d

C-C

C-NC-C=O

399.8

530.5

531.5

Figure S3. (a) Survey XPS spectrum and high-resolution (b) O 1s, (c) N 1s, (d) C 1s XPS spectra of

AHA-capped La2(MoO4)3 nanosheets.

S5

Wavenumber (cm-1

)

1000200030004000

Tra

nsm

itta

nce

(%

)

20

40

60

80

100

1385

(-C-N-)

2910 (-CH2-)

813 (-MoO4

3-)

3744 (-NH2)

Figure S4. FTIR spectrum of 6-aminohexanoic acid-capped La2(MoO4)3 nanosheets.

S6

2-theta (degree)

20 30 40 50 60

Inte

nsity (

a.u

.)

(a)

(b)

(c)

(d)

* *(e)

Ag

(11

1)

Ag

(20

0)

Ag JCPDS-74-1828*

Figure S5. XRD patterns of the synthesized 10.0 wt.% Ag/oxide hybrid NC samples: (a) Ag/TiO2

nanobels, (b) Ag/In2O3 nanorods, (c) Ag/Y2O3 nanorods, (d) Ag/ZrO2 nanorods, (e) Ag/CeO2

nanocubes. The marked with “*” is indexed to the deposited face-center-cubic (fcc) metallic Ag

structure; and the other remained peaks are contributed to the corresponding oxide structure.

S7

2-theta (degree)

20 30 40 50 60

Inte

nsity (

a.u

.)

(a)

(b)

(c)

(d)

*

# #

#

Au

(11

1)

Ag

(11

1)

Ag

(20

0)

*

Ag JCPDS-74-1828

Au JCPDS-01-1174

(e)

Figure S6. XRD patterns of the synthesized 10.0 wt.% Ag/mixed oxide and 10.0 wt.% Au/mixed

oxide NC samples: (a) Ag/CoWO4, (b) Ag/MnWO4, (c) Au/CoWO4, (d) Au/MnWO4, (e)

Au/La2(MoO4)3. The marked with “*” and “#” are indexed to deposited face-center-cubic (fcc)

metallic Ag and Au structures, respectively, and the other remained peaks are contributed to the

corresponding mixed oxide structure.

S8

Binding Energy (eV)

448 450 452 454 456 458 460

Inte

nsity (

CP

S)

Binding Energy (eV)

366 367 368 369 370

Inte

nsity (

CP

S)

Ag@TiO2

Pure Ag

Ti 2p

Ag 3d5/2367.7

368.0

(a)

(b)

Figure S7. (a) Ti 2p XPS spectra of 9.5 wt.% Ag/TiO2 nanohybrids; (b) Ag 3d XPS spectra of pure

9.5 wt.% Ag/TiO2 nanohybrids and pure Ag nanoparticles.

S9

Binding Energy (eV)

526 528 530 532 534

Inte

nsity (

CP

S)

Ti-O-Ti

HO-Ti

Figure S8. O 1s XPS spectrum of 9.5 wt.% Ag/TiO2 nanohybrids.

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0

1

2

3

0.0 0.2 0.4 0.6 0.8 1.0

Relative Pressure (P/Po )

Vo

lum

e A

ds

orb

ed

(m

l/g

)

Figure S9. Nitrogen adsorption-desorption of 9.5 wt.% Ag@TiO2 hybird nanobelts after annealing at

550 oC for 3 h.

S11

Wavelength (nm)

550 600 650 700 750

Ab

so

rba

nce

(a

.u.)

0.0

0.1

0.2

0.3

0.40 min

20 min

40 min

80 min

60 min

UV

irr

adia

tion

Irradiation Time (min)

0 20 40 60 80

C/C

o

0.0

0.2

0.4

0.6

0.8

1.0

Ag/TiO2 nanobels

TiO2 nanobels

P25

Ag/P25

B

A

Figure S10. (A) UV-vis absorption spectra of a methylene blue (MB) solution as a function of

irradiation time in the presence of 9.5 wt.% Ag/TiO2 hybrid NC catalyst and (B) comparison of the

MB photodegradation using TiO2 nanobels, commercial P25, 9.5 wt.% Ag/TiO2 hybrid NCs, and 9.5

wt.% Ag/P25 as photocatalysts.

S12

hv

Scheme S1. Proposed band structure and photocatalytic mechanism for light-induced charge

separation in Ag/TiO2 hybrid nanobelts.