High-Yield Synthesis of SiC@SiO2 Core–Shell Nanowires on Graphite Substrates for Energy Applications

High-purity silicon carbide @ silicon oxide core–shell nanowires (SiC@SiO2 NWs) were prepared on graphite substrates by a thermal evaporation method. Amorphous SiO2 coats with high chemical activity were obtained on the surface of silicon powders by wet oxidation. The effects of the oxidation time of silicon powders on the morphology and productivity of SiC@SiO2 NWs were investigated. The growth of SiC@SiO2 NWs follows the vapor–solid pattern, and the growth mechanism has been elucidated. The results showed that the yield of SiC@SiO2 NWs was enhanced by ∼654% with the wet oxidized silicon source compared to the preoxidation. The morphology and thickness of SiO2 coats play an important role in the yield and stacking fault (SF) density of SiC@SiO2 NWs. This work provides a feasible and optimal process for the preparation of high-yield SiC@SiO2 NWs.