Growth of SiC nanowiresanorods using a Fe-Si solution method

摘要

A new solution technique to grow SiC nanowiresanorods was developed by simply heating Fe-Si melt on a graphite plate in argon atmosphere to 1600 deg C for 3 and 6 h. SiC nanowiresanorods with diameters of 100 nm and lengths of several tens of micrometres were grown on the surface of the melt. The prototype of the nanowiresanorods is 3C-SiC (/6-SiC), and the growth direction is [111] for 3C-SiC. Taking into consideration the action of Fe in Fe-Si melt and the possible participation of oxygen, the growth mechanism of the SiC nanowires is proposed. It is believed that the formation of SiC nanowires is a combination of the solid-liquid-solid (SLS) reaction for nucleation and the vapour-liquid-solid (VLS) process for nanowire growth. In the SLS reaction, graphite carbon (solid) dissolved in the Fe-Si melt (liquid), and then reacted with the silicon in the melt to form SiC nuclei (solid). In the VLS reaction, SiO and CO (vapours) dissolved in the melt droplets (liquid) attached to the tip of the growing SiC nanowires (solid), and reacted to make them grow further.