Controlling Gold Nanoparticles with Atomic Precision
Controlling nanoparticles with atomic precision has long been a major goal in nanoscience research. Gold nanoparticles are particularly attractive due to their chemical stability and elegant optical properties. The synthesis of atomically precise gold nanoparticles, however, remained a major challenge in the pastresearch, which hampered the pursuit of fundamental science of such nanoparticles (e.g. surface structure, quantum size effect). This talk will present a size-focusing methodology successfully developed for synthesizing a series of atomically precise gold nanoparticles protected by thiolates (denoted as Aun(SR)m, with n ranging from a few dozens to several hundreds, also called nanoclusters).
Such ultrasmall nanoparticles (ca. 1-3 nm) exhibit distinct quantum size effects and interesting electronic/optical properties, which are fundamentally different from those of larger counterparts plasmonic nanoparticles. New types of atom-packing structures have been discovered in Aun(SR)m nanoclusters through X-ray crystallographic analysis. A few representative, size-specific Aun(SR)m nanoclusters will be discussed in detail. These well-defined nanoclusters also hold potential in catalysis as new model catalysts, and atomic-level correlation of the catalytic properties of Aun(SR)m with crystallographic structures will ultimately offer fundamental understanding on nanogold catalysis.