The silica-based sol-gel materials were prepared with various gold nano-particles ranging from 5 nm to 100 nm in diameter. Due to degradation of gold colloidal particles under strong acidic condition, the interaction of gold nano-particles with an acid could be monitored by a drastic red shift of SPR (Surface Plasmon Resonance) band. The rate of shift was converted to the diffusion rate of acid. The effect of the diffusion rate of aqueous acid solution was examined as a function of sizes of encapsulated gold nano-colloidal particles. The analytical fit concluded that the maximum rate was found at 15 nm of gold colloid. On the other hand, 60 nm gold colloid was expected to almost stop the acid diffusion. It was speculated that the surface of these gold colloids was homogeneously surrounded by the silica gel homogeneous layer, resulting in avoiding direct interaction with the acid and the surface of gold colloid. The size of 60 nm was estimated to be a close match of the average size of the cavity, which homogeneously covers the surface of the gold colloidal surface.<br/>

Controlling acid diffusion rate into gold nano-particle doped silica-based sol–gel material

2019 Fall National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.