Metal-Oxide Nanostructures Adriana-Gabriela PLĂIAŞU, Nicolae-Doru STĂNESCU
University of Pitesti, Faculty of Mechanics and Technology Introduction
Results
The nanotechnology offers opportunities in creating new features and functions. Several methods are available for the production of nanopowders production. The objective of this paper is to offer an introduction to the fundamentals of nanotechnology and nanopowder production using solar energy. Solar energy as a renewable energy is one of the sources that remain to be exploited in the future. In order to achieve the above-mentioned goals, literature research has been the starting point. The basic principle involved in the production of nanopowders consists Elaboration by SPVD in using a solar reactor to produce nanostructured powders underorsun energy The solar physical vapor deposition Solar PVD starting from micropowdres. (SPVD) is ancommercial original process to prepare nanopowders developed at Odeillo/Font Romeu The reactors are constituted by glass balloons, A target, made by the material to be melted and vaporized or sublimated (depending on its nature), is placed on a cooled support at the focus of the concentrator mirror Collection by a cold finger and pumping through a filter
Fig.1. Reactor with solar energy 5000 v.c.HY-ZnO 20 Torr filtre R v.c.HY-0.05% Al-ZnO 20 Torr filtre R v.c.HY-1% Al-ZnO 20 Torr filtre R v.c.HY-2.5% Al-ZnO 20 Torr filtre R v.c.HY-4% Al-ZnO 60 Torr filtre R v.c.HY-10% Al-ZnO 20 Torr filtre R
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Fig.2. X-ray diagrams of the nano powders synthesized with solar energy
All the synthesized powders were characterized by XRD,SEM and TEM observation in order to obtain information about crystallographic and morphology data strictly in correspondence with solar flux and pressure in solar reactor.
Fig. 3. SEM image of (a) pure ZnO nanoparticles and doped with (b) 1% mol Al (c) 2.5%mol Al (d) 10%mol Al
Fig. 4. TEM image of (a) pure CuO nanoparticles and doped with (b) 1% mol Mn (c) 2.5%mol Mn (d) 10%mol Mn
Several types of nanopowders were prepared in order to know the influence of the grain size on the known properties of materials. From these nanopowders it is possible to prepare films or coatings or massive nanomaterials. If new properties appear, especially at small grain size such as nanopartcicles, is important to choose appropriate method for synthesis correlated to morphology.
This domain of interest can open new fields of research. Our paper reports ZnO and CuO nanostructures with controlled size and shape which have been synthesized by physical vapor deposition using solar energy.
All authors are grateful to SOLFACE and SFERA, 7th EUprograms, which has provided opportunities to collaborate with researchers from France working with the Odeillo solar facilities on close fields.