Synthesis of SiOx Nano-Powders Using a Microwave Plasma Torch at Atmospheric Pressure

Abstract

The silicon oxide nano-powders (SiO x -NPs) were obtained in an atmospheric microwave plasma torch using a gas-phase silicon tetrachloride (SiCl 4 ) with N 2 and H 2 . The gas-phase SiCl 4 was injected with H 2 gas into the microwave plasma torch generated by N 2 and air swirl gas, and then the dark brown powders were deposited on the inner wall of a quartz tube. The sample was analyzed by an X-ray photoelectron spectroscopy (XPS), a scanning electron microscope (SEM), an energy dispersive spectrometer (EDS), and an X-ray diffraction (XRD). The average size and oxidation x values of synthesized SiO x -NPs were approximately 230 nm and 0.91, respectively. Furthermore, the volumetric charge capacity is 1127 mAh/g and has 89.2% retention after 100 cycles.