Ta2O5 Crystalline Nanoparticle Synthesis by DC Anodic Arc in Water

In the present study, Ta2O5 crystalline nanoparticles are produced in an appreciable volume using a quite simple anodic arc-discharge in the water system supplied with moderate dc power (<1 kW). To the best of our knowledge, these nanoparticles of high technological interest are for the first time produced by such gas-phase method. The system is characterized in real-time, during the nanoparticle formation, by electrical measurements, optical emission spectroscopy, and indicative high speed imaging, demonstrating the physicochemical processes that lead to supersaturated vapors promoting crystal growth. The product is extensively considered by high resolution transmission electron microscopy, X-ray crystallography, X-ray photoelectron spectroscopy, and particle size distribution measurements. Crystalline spherical nanoparticles with a structure that is stable at room temperature are identified. The importance of the present work consists in the possibility for full scale reliable production of dielectric nanoparticles useful, for instance, in the fabrication of composite materials with superior physical and chemical properties. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3391610] All rights reserved.