Preparation of mesoscopic gold rings and split rings by selective wetting of the contact points between the spheres within colloidal crystals
نویسندگان
چکیده
Rings and split rings of sub-micrometer size are prepared by the infiltration of colloidal crystals of spherical silica particles with diameters of about 1 lm by diluted solutions of tetrachloroauric acid in butanone, followed by the evaporation of the butanone, the annealing of the samples at elevated temperatures and the removal of the silica spheres with hydrofluoric acid. X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy and electron backscatter diffraction investigations reveal that the obtained rings and split rings are made out of metallic gold.
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