DC non-transferred arc plasmas are commonly used for nanoparticle production at commercial and laboratory scale. Plasma high temperature (around 10000 K) offers the possibility to vaporize a wide range of different precursors and to obtain very high cooling rates for the production of metal, oxide or composite nanoparticles. The typical approach in DC non-transferred arc torches is to inject solid, liquid or gaseous precursor materials in the tail of the plasma discharge, resulting in the formation of a vapour that is transported in a reaction chamber downstream the plasma torch. Nanoparticle nucleation occurs when vapour reaches the supersaturated state in colder regions in the reaction chamber, where additional quenching gas or carrier gas can be injected to control particle formation and to prevent nanoparticle deposition on the walls.
展开▼
