The efficient fabrication of nanoparticles will play a major part in the chemical industry.
Nanoparticles can be manufactured using numerous methods including spray pyrolysis, precipitation, hydrothermal synthesis, and thermal decomposition. But, the production processes cannot be scaled easily and include costly precursors, harmful chemicals, and a time-consuming and complicated series of production steps. Supercritical water hydrothermal production is simple, naturally scalable and chemically more efficient than current technology.
The University of Burgundy (France) researchers discovered a hydrothermal production process for continuous generation of hydroxide and oxide nanoparticles under supercritical state. Aqueous solutions of metal salt are dissolved in preheated water to achieve the supercritical state using a patented flow type tubular reactor. Owing to the increased reaction rate of hydrothermal production and low metal oxide solubility, a very high level of supersaturation is achieved soon after mixing, which results in the formation of particles with nanometer dimensions. Recently Dr. Frédéric Demoisson along with his coworkers discussed about several well-crystallized nanoparticles in the journal Advanced Engineering Materials.
Demoisson and co-workers, in their studies, created several nanopowders at a production rate of 10g/hr or above. Nanoparticles of ZrO2, ZnO, CeO2, and TiO2 can be synthesized directly following the suspension treatment. La2O3 and Y2O3 nanopowders can be produced following calcination of the hydroxides. As a result, well-crystallized nanoparticles of high-purity with a uniform size distribution can be observed using surface area analysis, TEM, and XRD.
The scientists aim to gain an overall understanding of chemical and physical properties of nanomaterials. They hope to determine the morphology and size of nanoparticles prior to the synthesis.
Source: http://icb.u-bourgogne.fr/