Structural verification and optical characterization of SiO sub(2)-Au-Cu sub(2)O nanoparticles

In this paper, SiO sub(2)-Au-Cu sub(2)O core/shell/shell nanoparticles were synthesized by reducing gold chloride on 3-amino-propyl-triethoxysilane molecules attached silica nanoparticle cores for several stages. Cu sub(2)O nanoparticles were synthesized readily with the size of 4-5 nm using a simple route of sol-gel method Then, they were clung to the surface of Au seeds. The morphology of the resultant particles was studied using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Transmission electron microscopy images demonstrate growth of monodispersed gold seeds and Cu sub(2)O nanoparticles in narrow size up to 10 nm and 5 nm, respectively. The presence of gold and Cu sub(2)O coating was confirmed by X-ray diffraction, Fourier transform infrared spectroscopy and UV-Vis spectroscopy. Absorption spectroscopy shows considerably 40 nm blue shift in absorption edge for SiO sub(2)-Au-Cu sub(2)O nanostructure rather than SiO sub(2)-Au core/shell nanoparticles.