C. Mahendiran, R. Ganesan, A. Gedanken
SHORT COMMUNICATION
also observed but we attribute it to surface adsorption of (40 mmϫ5 mm) reference electrode, and an ultrasonic tip as a
working electrode. In the synthesis, a cathodic current density of
100 mAcm was applied to a solution of 4 g of AlCl dissolved in
3
chloride ions on aluminum, as this is a well-known phe-
nomenon that has been studied in detail previously.
–
2
[
27]
4
80 mL of a 1.0 solution of LiAlH in THF for 4 h. The duration
Samples for TEM and HRTEM were prepared by ultra-
sonically dispersing the product into absolute ethanol, then
by placing a drop of this suspension onto a copper grid
coated with an amorphous carbon film supported by filter
paper, and by drying in air. Figure 3a presents the images
of the current pulse was 600 s, and the off time of the current pulse
was 60 s. The duration of the ultrasonic pulse was 240 ms. The
ultrasound power intensity was 76 W. The resulting metallic alumi-
num product was washed several times with THF and dried under
vacuum. The need for such a long duration for the electric pulse
of TEM measurements of the products obtained in THF. was dictated by the low current. The yield of the product is 53.0%,
The obtained images show the formation of small and ag- measured in respect to the total number of coulombs passed
gregated particles in the range 10–20 nm. Figure 3c presents through the solution.
the HRTEM images of Al nanoparticles. It illustrates the
well-defined lattice fringes, indicating the crystalline nature
The product was deposited on the cathode and was characterized
as aluminum by XRD measurements. The particle morphology was
of the Al nanoparticles. The measured interplanar spacing studied with HRSEM, TEM (JEOL-2010), and HRTEM (JSM-
d value is 2.35 Å, which corresponds to the lattice plane of 7000F HR).
(111). These values are in agreement with the reported
JCPDS value of d111 = 2.33 Å (JCPDS No. 004-0787). The
selected area electron diffraction (SAED) pattern (Fig-
ure 3d) shows the formation of ring patterns, which infer
the polycrystalline behavior of the materials and confirms
that the metal is Al.
Acknowledgments
This work was carried out with the support of the European Com-
munity Sixth Framework Program through a STREP Grant to the
SELECTNANO Consortium, Contract No. 516922.03/25/2005.
Conclusions
[
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[
[
[
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where.
In brief, all the sonoelectrochemical measurements were
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[
[
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