Gold decoration of silica by decomposition of aqueous gold(III) hydroxide at low temperatures

M. A. MACCHIONE; J. E. SAMANIEGO; R. MOIRAGHI; N. PASSARELLI; V. A. MACAGNO; E. A. CORONADO; M. J. YACAMAN; M. A. PÉREZ

RSC Advances

Royal Society of Chemistry

Año: 2018 vol. 8 p. 19979 - 19979

2046-2069

he decomposition of gold hydroxide to give metallic gold is known to take place around 300 °C in dry environments. However, little information about the gold hydroxide stability in wet environments has been recorded. Here, we present experimental evidence which shows that aqueous/water-enriched gold(III) hydroxide colloids decompose spontaneously to form gold nanoparticles at temperature values above the freezing point of water. Based on this reaction, we developed a method to decorate silica spheres with gold nanoparticles by precipitation and decomposition of gold(III) hydroxide onto the silica surface in wet media by a simple one-pot/one-step protocol. The silica|gold nanostructures are prepared in high yield and with a low level of by-products.