Oxide Nanoparticles Synthesized in a Microwave Plasma Torch

Nanomaterials have attracted considerable attention from researchers, since the discovery of carbon nanotubes by Iijima. Due to their peculiar structural characteristics and size effects, nanomaterials exhibit some novel physical properties that are different from those of the bulk materials. In this work, we described a synthesis method of cadmium oxide (CdO), zinc oxide (ZnO) and carbon black (CB) using a microwave plasma torch and characterized the as-synthesized CdO, ZnO and CB. CdO and ZnO were synthesized by making use of an oxygen microwave plasma torch at atmospheric pressure. Cadmium and zinc meshes in solid were used as starting materials. The as-produced CdO nanopowder consisted of typical nano-cubic structures and the mean crystallite size was approximately 48 nm. The ZnO nanopowders synthesized consisted of nanorods from 100 to 200 nanometers in length. CBs were synthesized with different N2 contents in a gas mixture by a microwave plasma torch at atmospheric pressure. Methane (CH₄) as a source of carbon atoms was directly injected into the microwave plasma torch. The CBs were mainly thornbush-shaped and turbostratic structures. Finally, the oxide nanoparticles were characterized by X-ray diffractometer (XRD), field emission scanning electron-microscope (FESEM) and field-emission transmission electron-microscopy (FETEM).