Preparation and Functionalization of Gold Nanoparticles

The abilities to control the size of gold nanoparticles and to manipulate them on a nanometer scale are priority subjects in the field of nanotechnology. To synthesize gold nanomaterials in controlled sizes and dimensions, various approaches have been developed. These systems can be made up of several different microenvironments: a continuous medium formed by the alkane or water, a disperse phase formed by microdroplets, micelles or surface active compounds and a tensioactive film, which separates the hydrophilic phase from the alkane and allows the solubilization to occur. Micelle or microemulsion approach allows for a unique encapsulated volume of controllable size through which reactions and subsequent development of metal and metallic compounds can be produced. The precipitation of prime nanoparticles is based on the supersaturation of solution by reactants and stabilization of formed nanoparticles by surfactants. The existence of these microenvironments gives these systems a particular ability to modulate the chemical reactivity due to the compartmentalization of the reactants in different microenvironments. These nanoparticles have become the focus of intensive research due to their unique applications in mesoscopic physics and in the fabrication of nanoscale devices.