Carbothermal synthesis of alpha-SiC micro-ribbons

We report the synthesis of microscopic alpha-SiC ribbons (belts) on the surface of a graphite rod at 1800 degrees-1900 degrees C by a carbothermal process. The width of the ribbons produced ranged from 500 nm to 5 mu m and the aspect ratio was up to 400. The ribbon thickness ranged from 50 to 800 nm. Their growth mechanism was explained by accelerated growth along the twin boundary. SiC whiskers grew on the rod along with the ribbons. Frequently, ribbons were growing from the tip of a whisker or whiskers were growing from the edge of a ribbon. SiC ribbons may find applications in high-temperature sensors, photo-electronic devices, or robust cantilevers in micro (or nano) electro mechanical systems. Alternatively, they can be used as reinforcements in composite materials, conferring anisotropic mechanical properties, such as unidirectional flexibility, to the composite.