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Room temperature radiolytic synthesized Cu@CuAlO(2)-Al(2)O(3) nanoparticles.

Abedini A, Saion E, Larki F, Zakaria A, Noroozi M, Soltani N - Int J Mol Sci (2012)

Bottom Line: Results of transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD) showed that Cu@CuAlO(2)-Al(2)O(3) nanoparticles are in a core-shell structure.By controlling the absorbed dose and precursor concentration, nanoclusters with different particle sizes were obtained.The average particle diameter increased with increased precursor concentration and decreased with increased dose.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor 43400, Malaysia; E-Mails: elias@science.upm.edu.my (E.S.); farhad.larki@gmail.com (F.L.); azmizak@science.upm.edu.my (A.Z.); monir_noroozi@yahoo.com (M.N.); nayereh.soltani@gmail.com (N.S.).

ABSTRACT
Colloidal Cu@CuAlO(2)-Al(2)O(3) bimetallic nanoparticles were prepared by a gamma irradiation method in an aqueous system in the presence of polyvinyl pyrrolidone (PVP) and isopropanol respectively as a colloidal stabilizer and scavenger of hydrogen and hydroxyl radicals. The gamma irradiation was carried out in a (60)Co gamma source chamber with different doses up to 120 kGy. The formation of Cu@CuAlO(2)-Al(2)O(3) nanoparticles was observed initially by the change in color of the colloidal samples from colorless to brown. Fourier transform infrared spectroscopy (FTIR) confirmed the presence of bonds between polymer chains and the metal surface at all radiation doses. Results of transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD) showed that Cu@CuAlO(2)-Al(2)O(3) nanoparticles are in a core-shell structure. By controlling the absorbed dose and precursor concentration, nanoclusters with different particle sizes were obtained. The average particle diameter increased with increased precursor concentration and decreased with increased dose. This is due to the competition between nucleation, growth, and aggregation processes in the formation of nanoclusters during irradiation.

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FT-IR spectra of (a) pure PVP, and PVP-capped Cu@CuAlO2-Al2O3 nanoparticles at: (b) 80; (c) 100; and (d) 120 kGy radiation dose.
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f3-ijms-13-11941: FT-IR spectra of (a) pure PVP, and PVP-capped Cu@CuAlO2-Al2O3 nanoparticles at: (b) 80; (c) 100; and (d) 120 kGy radiation dose.

Mentions: Figure 3 presents a comparison of FT-IR spectra of PVP alone and PVP-capped Cu@CuAlO2-Al2O3 nanoparticles at doses of 80, 100, and 120 kGy. The spectra are given in the range 3000–400 cm−1, because the main chemical changes occurred in this range. In the spectrum of pure-PVP (Figure 3a), the peaks located at 1647, 1426, and 1279 cm−1, are assigned to the C=O stretching vibration, CH2 bending vibration, and C-N stretching vibration band, respectively [30–33]. The PVP molecules in aqueous solution may take resonance structures as shown in Figure 1b [24]. In the FT-IR spectrum of PVP-capped Cu@CuAlO2-Al2O3 nanoparticles (Figure 3b), compared to pure PVP (Figure 3a), the intensity of the C=O stretching band decreased, indicating on the formation of intermolecular bonds between PVP and shell. As shown in Figure 3b, the adsorption band appeared at 1016 cm−1 generally assigned to C-N, indicating the coordination between N and Cu@CuAlO2-Al2O3 nanoparticles. Compared to pure PVP, this peak was reduced due to the strengthened C–N bonds of the pyridine when the metal was incorporated. The change of the peak shape below 900 cm−1 is associated with the Al-O bond vibrations [34,35]. These peaks slightly increased with increasing dose, indicating the amount of that the oxide form of Al on the surface of Cu nanoparticles increased (Figure 3b–d).


Room temperature radiolytic synthesized Cu@CuAlO(2)-Al(2)O(3) nanoparticles.

Abedini A, Saion E, Larki F, Zakaria A, Noroozi M, Soltani N - Int J Mol Sci (2012)

FT-IR spectra of (a) pure PVP, and PVP-capped Cu@CuAlO2-Al2O3 nanoparticles at: (b) 80; (c) 100; and (d) 120 kGy radiation dose.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3472785&req=5

f3-ijms-13-11941: FT-IR spectra of (a) pure PVP, and PVP-capped Cu@CuAlO2-Al2O3 nanoparticles at: (b) 80; (c) 100; and (d) 120 kGy radiation dose.
Mentions: Figure 3 presents a comparison of FT-IR spectra of PVP alone and PVP-capped Cu@CuAlO2-Al2O3 nanoparticles at doses of 80, 100, and 120 kGy. The spectra are given in the range 3000–400 cm−1, because the main chemical changes occurred in this range. In the spectrum of pure-PVP (Figure 3a), the peaks located at 1647, 1426, and 1279 cm−1, are assigned to the C=O stretching vibration, CH2 bending vibration, and C-N stretching vibration band, respectively [30–33]. The PVP molecules in aqueous solution may take resonance structures as shown in Figure 1b [24]. In the FT-IR spectrum of PVP-capped Cu@CuAlO2-Al2O3 nanoparticles (Figure 3b), compared to pure PVP (Figure 3a), the intensity of the C=O stretching band decreased, indicating on the formation of intermolecular bonds between PVP and shell. As shown in Figure 3b, the adsorption band appeared at 1016 cm−1 generally assigned to C-N, indicating the coordination between N and Cu@CuAlO2-Al2O3 nanoparticles. Compared to pure PVP, this peak was reduced due to the strengthened C–N bonds of the pyridine when the metal was incorporated. The change of the peak shape below 900 cm−1 is associated with the Al-O bond vibrations [34,35]. These peaks slightly increased with increasing dose, indicating the amount of that the oxide form of Al on the surface of Cu nanoparticles increased (Figure 3b–d).

Bottom Line: Results of transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD) showed that Cu@CuAlO(2)-Al(2)O(3) nanoparticles are in a core-shell structure.By controlling the absorbed dose and precursor concentration, nanoclusters with different particle sizes were obtained.The average particle diameter increased with increased precursor concentration and decreased with increased dose.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor 43400, Malaysia; E-Mails: elias@science.upm.edu.my (E.S.); farhad.larki@gmail.com (F.L.); azmizak@science.upm.edu.my (A.Z.); monir_noroozi@yahoo.com (M.N.); nayereh.soltani@gmail.com (N.S.).

ABSTRACT
Colloidal Cu@CuAlO(2)-Al(2)O(3) bimetallic nanoparticles were prepared by a gamma irradiation method in an aqueous system in the presence of polyvinyl pyrrolidone (PVP) and isopropanol respectively as a colloidal stabilizer and scavenger of hydrogen and hydroxyl radicals. The gamma irradiation was carried out in a (60)Co gamma source chamber with different doses up to 120 kGy. The formation of Cu@CuAlO(2)-Al(2)O(3) nanoparticles was observed initially by the change in color of the colloidal samples from colorless to brown. Fourier transform infrared spectroscopy (FTIR) confirmed the presence of bonds between polymer chains and the metal surface at all radiation doses. Results of transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD) showed that Cu@CuAlO(2)-Al(2)O(3) nanoparticles are in a core-shell structure. By controlling the absorbed dose and precursor concentration, nanoclusters with different particle sizes were obtained. The average particle diameter increased with increased precursor concentration and decreased with increased dose. This is due to the competition between nucleation, growth, and aggregation processes in the formation of nanoclusters during irradiation.

Show MeSH