Abstract
A micellar method has been used to prepare silver-coated cobalt (Co@Ag) nanoparticles. The synthesized particles have been deeply characterized by several methods, i.e., XRD, UV–Vis, TEM, XPS, and electrochemical techniques. There is every indication that the obtained particles show a truly core–shell structure. All the nanoparticles obtained under different conditions are in the size range 3–5 nm. High-resolution TEM (HRTEM), Fast Fourier Transformation (FFT), and Selected Area Electron Diffraction (SAED) indicated that the presence of hcp-Co and fcc-Ag, in which cobalt is located in the central area; meanwhile silver is at the edges of the nanoparticle. The absorption band of the Co@Ag colloid shifts to a longer wavelength and broadens relative to that of pure silver colloid. Voltammetric characterization allowed to determine the coverage of the cobalt core.
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Acknowledgments
The authors are grateful to Dr. J. Solla-Gullón for their helpful support in the preparation of the nanoparticles. This article was supported by contract MAT-2006-12913-C02-01 from the Comisión Interministerial de Ciencia y Tecnología (CICYT). J. García-Torres would also like to thank the Departament d’Innovació, Universitats i Empresa of the Generalitat de Catalunya and Fons Social Europeu for their financial support.
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Garcia-Torres, J., Vallés, E. & Gómez, E. Synthesis and characterization of Co@Ag core–shell nanoparticles. J Nanopart Res 12, 2189–2199 (2010). https://doi.org/10.1007/s11051-009-9784-x
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DOI: https://doi.org/10.1007/s11051-009-9784-x