Synthesis of hybrid gold-gold sulfide colloidal particles
Idioma
en
Article de revue
Este ítem está publicado en
Langmuir. 2008, vol. 24, n° 8, p. 4289-4294
American Chemical Society
Resumen en inglés
The nucleation and growth mechanism of nanometer size gold onto gold sulfide colloidal particles by irradiation-induced reduction is reported. The process is characterized by ultraviolet-visible spectroscopy, electronic ...Leer más >
The nucleation and growth mechanism of nanometer size gold onto gold sulfide colloidal particles by irradiation-induced reduction is reported. The process is characterized by ultraviolet-visible spectroscopy, electronic diffraction, and high-resolution transmission electron microscopy, allowing for observation of several key intermediates and characteristics of the growth mechanism. The formation mechanism of gold on the surface of the gold sulfide particles is shown to depend strongly on the deposition rate. At low dose rate, gold nucleates preferentially onto specific gold-rich Au2S facets {110}, resulting in epitaxial growth. The gold crystal lattice plastically deforms near the interface to accommodate a substantial lattice mismatch. Upon increasing gold precursor concentration, this low dose rate results in growth of elongated gold island on the gold sulfide surface. At a high dose rate, several randomly oriented gold particles are simultaneously produced on gold sulfide, resulting in a layered structure. The absorption spectra of these particles show a dominant surface plasmon band, whose peak wavelength shifts markedly to the red as layered structure is formed.< Leer menos
Palabras clave en inglés
Growth mechanism
Nucleation
Gold
Nanoparticles
Colloids
Sulfide
UV spectroscopy
Electron diffraction
Transmission electron microscopy
Orígen
Importado de HalCentros de investigación