2014-Sustainable Industrial Processing Summit
SIPS 2014 Volume 5: Composite, Ceramic, Quasi-crystals, Nanomaterials & Coatings
| Editors: | Kongoli F |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2014 |
| Pages: | 578 pages |
| ISBN: | 978-1-987820-07-2 |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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Microstructure, mechanical and chemical properties of Au/SiO2 composites
Alena Reznickova1;1ICT PRAGUE, Prague, Czech Republic;
Type of Paper: Regular
Id Paper: 52
Topic: 16
Abstract:
Metal nanoparticles on oxide substrates have gained a markedly increasing consideration with regard to both scientific and technological purposes. Significant variations in the Au/SiO2 optical and mechanical response are induced by modifications of the system morphology from cluster-like systems, where gold nanoparticles are dispersed on the silica surface, to island-like structures, where Au aggregates are partially interconnected between each other, and ultimately, to continuous films.
Properties of gold films sputtered under different conditions onto borosilicate glass substrate were studied. The mechanical properties of sputtered gold layers were examined using nanoindenter. The surface elastic modulus and hardness were determined and scratch tests were performed. XRD analysis provided information about the gold crystalline nano-structure. XRD method was employed to determine surface texture, crystallite size and microstrain. The study of mechanical properties of Au/SiO2 was supported by measurement of its chemical composition. Depth concentration profile of oxygen in gold silica nanosystem was determined from RBS spectra. The surface morphology was examined by Atomic Force Microscopy and by Scanning Electron Microscope.
The elastic modulus decreases rapidly from the surface up to the depth of ca 20 nm. The dependence of the hardness on the tip displacement into the surface indicates dramatic hardness decline. Sputtering of gold on glass substrate leads to formation of polycrystals with a preferential orientation in the (111) direction. The concentration of oxygen decreases monotonously with increasing depth. With ongoing deposition, interconnections between individual clusters are formed and the deposited layer becomes homogeneous and uniform.