Photonic crystals in biology

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Poster Session, Tuesday, June 15
Theme A1 - B702
1
Coated Multi-Walled Carbon Nanotubes with Ceria Nanoparticles
1
Evgeniya Koval’s’kaP
PO.O. Chuiko Institute of Surface Chemistry, Nat. Acad. f Sci. of Ukraine; 17, Gen. Naumov Str., Kyiv 03164, Ukraine
Abstract-The composites have been received by sedimentation of oxides on surface multi-wall carbon nanotubes (MWNTs). The
nanocomposites of were identified by transmission electronic microscope. The crystalline structure was verified by electron diffraction pattern
and X-ray spectroscopy. Also XPS spectra were performed on the MWNT samples.
The combination of carbon nanotubes (CNTs) with other
nanocrystals is expected to be useful for applications in
catalysts, sensors, nanoelectronic devices, polymer or ceramic
reinforcement. In the paper [1], the authors highlight
opportunities for decorating CNTs with a broad range of
functional metal oxides including CeR2ROR3R and/or CeOR2R, AlR2ROR3R,
LaR2ROR3R, in SC COR2R modified with ethanol. For example, the
nanocomposites of CNTs and cerium are very interesting for
further studies on their physical and chemical properties.
In this paper, the composites have been received by
sedimentation of oxides on surface multi-wall carbon
nanotubes (MWNTs) from solutions by a reaction:
4Ce(NOR3R) R3R 12NaOH + OR2R 4CeOR2R + 12NaNOR3 R+ 6HR2RO
.
A certificated catalytic MWNTs (Nanothinx S. A.) having
12–31 nm diameters, 15–35 walls and 97 % purity (about 2 %
is iron catalyst and less 1 % is pyrolytic carbon) was used. The
nanocomposites of CeRxRORyR/MWNTs were identified by
transmission electronic microscope (TEM), and their
crystalline structure was verified by the selected area electron
diffraction (SAED) pattern and X-ray spectroscopy.
Figure 1 shows the MWNTs. TEM images of modified
MWNTs show the ceria nanoparticles on the MWNTs surface.
The size of the particles is 6-10 nm. SAED indicates the rings
pattern of nanoparticles can be indexed using the facecentered
cubic polycrystalline structure of cerium oxides.
MWNT bundles were functionalized with hydroxyl and
carbonyl. The deposition of ceria particles on the MWNT
bundles depended on the surface state of the MWNT bundles.
We believe that the methodology described here expands the
Intensity (a.u.)
Intensity (a. u.)
20000
15000
10000
5000
Ce3d
O1s
1000 800 600 400 200 0
Binding energy (eV)
C1s
MWNTs
a
Ce x O y (5.2%)/MWNTs
Ce x O y (31%)/MWNTs
Intensity (a.u.)
8000
6000
4000
2000
C-O
C-C
C=O
O-C=O
0
280 284 288 292 296 300
Binding energy (eV)
12000 C-C
c
8000
C-C
d
9000
6000
6000
4000
3000 C-O C=O
O-C=O 2000
C-O
0
280 284 288 292 296 300
0
280 284 288 292 296 300
Binding energy (eV)
Binding energy (eV)
Intensity (a.u.)
C=O O-C=O
s (c).
(d).
Figure 2. Total XPS spectra of the purified MWNTs,
CeRxRORyR(5.2%)/MWNTs and CeRxRORyR(31%)/MWNTs (a). XPS
spectrum of carbon (C1s) in the purified MWNTs (b). XPS
spectrum of carbon (C1s) in the CeRxRORyR(5.2%)/MWNTs (c).
XPS spectrum of carbon (C1s) in the CeRxRORyR(31%)/MWNTs
b
functionality chemistry of CNTs and opens up a new avenue
for coating one-dimensional nanostructures with various metal
oxides and construction of designed nanoarchitectures.
Figure 1. TEM images of MWNTs (a), modified MWNTs by
ceria (5.2 %, b) and modified MWNTs by ceria (31 %, c).
To further investigate the surface state of the MWNTs and
the mechanism of ceria coating on the MWNTs, XPS spectra
were performed on the MWNT samples. Figure 2 shows the
XPS spectra of the purified MWNTs and the ceria-coated
CeRxRORyR(5.2%)/MWNTs and CeRxRORyR(31%)/MWNTs, respecttively.
The atomic ratio of Ce/O/C in the sample
CeRxRORyR(5.2%)/MWNTs calculated from the XPS spectrum is
about 1.1 : 1 : 18 and in the sample CeRxRORyR(31%)/MWNTs is
about 1.1 : 1 : 3.6 which indicates that there are still large
amount of functional groups on the surface of the MWNTs
after the deposit process.
Ceria nanoparticles with diameter of about 6–10 nm were
successfully deposited on the MWNT bundles by a chemical
reaction of Ce(NOR3R)R3R with NaOH solution. The synthesis was
done in the aqueous solution at room temperature that reduces
cost of the preparation procedure of nanosized ceria. The
*Corresponding author: evgeniya1209@ukr.net
[1] Z. Sun, X. Zhang, B. Han, Y. Wu, G. An, Z. Liu, S. Miao, Z.
Miao, Carbon 45, 2589 (2007).
6th Nanoscience and Nanotechnology Conference, zmir, 2010 411