Abstract
In-flight microplasma synthesis of luminescent silicon nanocrystals (Si-NCs) is presented. A mixture of SiCl_4 and H_2 is activated in the high pressure (10 kPa), miniaturized non-thermal plasma reactor. High pressure condition accelerates cluster nucleation via three-body reaction, while a miniaturized reactor suppresses excess crystal growth due to short residence time, leading to 3-5 nm crystalline nanoparticles: process yield of 30-100 mg/h of luminescent Si-NCs was demonstrated. Crystallinity of as-produced silicon nanoparticles increased with increasing either input power or initial H2 content in the feed gas. Strong photon absorption in the short wavelength (less than 450 nm) and associated red-photo luminescence due to quantum confinement effect was confirmed.
