Synthesis of nano-sized tin oxide powder by argon plasma jet at atmospheric pressure

Nano-sized SnO2 particles were prepared with an argon plasma jet using SnCl4 and O-2 as raw materials. SnCl4, which was easily vaporized at room temperature, and O-2 were injected into the reactor through the reaction tube in the vapor phase by an Ar-carrier gas. The product of the reaction with the argon plasma jet was synthesized by rapid quenching. Most of the prepared powders were collected on an inside wall of the reactor. Because this process does not need any other after-treatment, SnO2 powder could conveniently be synthesized. As a process parameter, the flow rate of oxygen gas was kept below the constant flow rate of the carrier gas and additional nitrogen gases. The characteristics of the powders were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). TEM and SEM analysis found the particle sizes of SnO2 to be from 3 nm to 20 nm, and images of the particles were also produced. The cross stripes on SnO2 powder also have been studied. The effects of O-2 parameters were investigated to optimize synthesis of tin oxide with XRD analysis. An increase in O-2 concentration does not ensure good results; therefore it was possible to find optimum conditions for synthesis of SnO2 particles. (C) 2008 Elsevier B.V. All rights reserved.