Growth of SiC nanowires by low pressure chemical vapor infiltration using different catalysts

SiC nanowires were synthesized by LPCVI using different catalysts, and the influences of input gas ratio (α) and catalysts were investigated. The average diameter firstly decreased and then increased with increasing α. Under Ni-based catalysis, SiC nanowires were long and thin, and increased with increasing concentration; under Fe-based catalysis, they were short and thick, and the influence of concentration could be neglected. The growth of SiC nanowires was controlled by vapor-liquid-solid (VLS) growth mechanism and the liquid-solid interface between nanowire and metal droplet was the growth plane. At same concentration, the diameter grown under Ni-based catalyst decreased with decreasing diameter of catalyst droplet, while under Fe-based catalyst, the diameters were not affected by catalyst droplet because of the high concentration. SiC nanowires were synthesized in 2D C/SiC composites and could enhance the mechanical properties effectively because of energy consuming from the fracture, pulled up and debond of SiC nanowires.