Optical Property/Structure/Process Relationship for Gold Nanoparticles

Clarkson University, Potsdam NY

Investigators

Abstract

Proposal Title: Optical Property/Structure/Process Relationship for Gold Nanoparticles Proposal Number: CTS-0094773 Principal Investigator: Ian Suni Institution: Clarkson University The objective of this proposal is to investigate the electrodeposition of gold particles onto hydrogen terminated silicon surfaces using atomic force microscopy, second harmonic generation (SHG), and UV-visible extinction spectroscopy. Gold nanoparticles will be deposited onto silicon substrates by both electrodeposition and by galvanic displacement from hydrogen fluoride solutions. The electrodeposition of metal nanoparticles of a relatively uniform size can be accomplished by using a large transient overpotential so that instantaneous nucleation occurs. Nanoparticle size can be controlled by regulating the duration of the nucleation transient. An alternative method of nanoparticle growth is to apply a highly cathodic voltage transient as a nucleation strike, followed by particle growth at a low overpotential so that further nucleation does not occur. The optical studies involve development of in situ tools for studying nucleation and particle growth during the initial stages of thin film deposition. Gold nanoparticles have unique optical and catalytic properties that might lead to novel applications. The recent emergence of gold nanoparticles as effective oxidation catalysts is an area where this work may have relevance. In addition, this work may lead to novel methods to rapidly characterize the average size and structure of metal nanoparticles over micron-sized length scales.