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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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XRD patterns of Cu@CuAlO2-Al2O3 nanoparticles at 120 kGy for various ion concentrations: (a) 5.0 × 10−5; (b) 5.4 × 10−5; (c) 5.7 × 10−5; (d) 6 × 10−5; and (e) 6.4 × 10−5 mol/mL.
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f9-ijms-13-11941: XRD patterns of Cu@CuAlO2-Al2O3 nanoparticles at 120 kGy for various ion concentrations: (a) 5.0 × 10−5; (b) 5.4 × 10−5; (c) 5.7 × 10−5; (d) 6 × 10−5; and (e) 6.4 × 10−5 mol/mL.

Mentions: X-ray powder diffraction diagrams of Cu@CuAlO2-Al2O3 colloids, presented in Figure 9. As can be observed, at lower precursor concentration of zero-valent state copper and alumina reflections was found. The alumina layer mostly covered the Cu core, thus protecting it from corrosion. The oxidation of Al may results in a slight inevitable surface oxidation during the process of washing and drying. By increasing ion concentration, the thickness of the alumina layer that coated the Cu core increased, which can affect the crystallinity of Cu. Therefore, the count of reflection peaks of Cu decreases with increasing ion concentration. The XRD diagram for sample with the highest ion concentration clearly shows that the sample is entirely amorphous (Figure 9e).


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)

XRD patterns of Cu@CuAlO2-Al2O3 nanoparticles at 120 kGy for various ion concentrations: (a) 5.0 × 10−5; (b) 5.4 × 10−5; (c) 5.7 × 10−5; (d) 6 × 10−5; and (e) 6.4 × 10−5 mol/mL.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f9-ijms-13-11941: XRD patterns of Cu@CuAlO2-Al2O3 nanoparticles at 120 kGy for various ion concentrations: (a) 5.0 × 10−5; (b) 5.4 × 10−5; (c) 5.7 × 10−5; (d) 6 × 10−5; and (e) 6.4 × 10−5 mol/mL.
Mentions: X-ray powder diffraction diagrams of Cu@CuAlO2-Al2O3 colloids, presented in Figure 9. As can be observed, at lower precursor concentration of zero-valent state copper and alumina reflections was found. The alumina layer mostly covered the Cu core, thus protecting it from corrosion. The oxidation of Al may results in a slight inevitable surface oxidation during the process of washing and drying. By increasing ion concentration, the thickness of the alumina layer that coated the Cu core increased, which can affect the crystallinity of Cu. Therefore, the count of reflection peaks of Cu decreases with increasing ion concentration. The XRD diagram for sample with the highest ion concentration clearly shows that the sample is entirely amorphous (Figure 9e).

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