Influence of charging in feedstock particles injected into modulated induction thermal plasma for nanoparticle synthesis with OML theory

This report investigated influence of electric charging in feedstock particles injected in modulated induction thermal plasma (MITP) for nanoparticle synthesis. Charging feedstock particles can affect heating efficiency and evaporation rate, nanoparticle formation. The electric charging effect in feedstock particles was calculated on the basis of orbital motion limited (OML) theory with thermionic electron emission and secondary electron emission. The developed model was adopted to "MITP+TCFF method" in which modulated induction thermal plasma provides a periodical changed temperature and gas flow fields with intermittent feedstock feeding for synthesizing large amounts of nanoparticles. The Si feedstock was assumed to be supplied during on-time of MITP. Results indicated that feedstock particles were electrically charged in negative just after injection, while the particles have positive charge due to electron emission processes, which influences heating effect.