Dresden 2009 – wissenschaftliches Programm
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MM: Fachverband Metall- und Materialphysik
MM 42: Nanostructured Materials III
MM 42.4: Vortrag
Donnerstag, 26. März 2009, 14:45–15:00, IFW A
Gold nanoparticles under synchrotron X-rays — •Chang-Hai Wang1, Chi-Jen Liu2, Tzu-En Hua2, Chia-Chi Chien2, Wei-Hua Leng2, Shin-Tai Chen2, Cheng-Liang Wang2, and Yeu-Kuang Hwu2 — 1Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg - University, 55099 Mainz — 2Institute of Physics, Academia Sinica, Taipei, 11529 Taiwan
Gold particles with length scale less than 100 nm develop unique physical properties and biocompatible features that render extensive applications in nanotechnology. To materialize the functionalities, gold nanoparticles with controlled size, favorable surface properties and size distribution would be a pre-requisite. This work describes a new room-temperature synchrotron X-ray irradiation method to prepare reductant- and stabilizer-free colloidal gold solutions. Typical characterization tools include TEM, UV-VIS, FTIR, XRD and ICP-OES. The influence of processing parameters such as the pH value, exposure time, ionic strength and radical scavenger on the structure of gold nanoparticles was investigated. The mechanisms underlying the X-ray-triggered reduction of gold ions and the formation of gold clusters are discussed in detail. An interesting morphological evolution as a function of exposure time, from cross-linked network-like structure to individual particles, has been discovered. This approach could be easily extended to the preparation of polymer-modified colloidal gold by simply adding the polymer species to the precursor solutions. As an implication for nanotechnology, the interactions between gold nanoparticles and cells are also studied and reported.