Synthesis of 3C-silicon carbide 1D structures by carbothermal reduction process

In this work, cubic 3C-silicon carbide (beta-SiC) 1D-structures were successfully synthesized at various temperatures (1600 °C, 1650 °C and 1700 °C) by using graphite flakes and microfine silica through the carbothermal reduction process. The grown SiC structures were observed with two distinct morphologies viz. ribbon-type (diameter 2–5 µm) and rod-type (diameter ≤ 2 µm). The ribbon-type morphology was formed on the surface of the graphite flakes at relatively low temperature (1600 °C) whereas, the rod-type morphology was formed at a higher temperature (≥1650 °C) between the interlamellar spacing of graphite flakes. The TEM analysis confirms the growth direction of [111] for the as-grown 3C-SiC structures. The growth process of these two distinct morphologies is discussed in terms of nucleation and precipitation associated with vapour-solid (VS) and vapour-liquid-solid (VLS) mechanisms. Moreover, Raman spectroscopy indicated that the corresponding peaks of the as-grown SiC structures had red shifted as compared to the bulk SiC and that could be attributed to the confinement effect, internal stresses in the structure and stacking faults.