Formation of hexagonal AlN nanotowers and layered nanorods by direct nitridation of aluminum

Hexagonal AlN nanotowers and layered nanorods with a diameter of hundreds of nanometers and a length of several microns have been successfully synthesized by direct nitridation of aluminum and rice bran mixture compacts in a tube furnace up to 1250 °C under a flow of nitrogen without the addition of extra catalyst. The structure of the nano-AlN products was characterized by XRD and SEM. XRD pattern indicates that the conversion of Al into AlN is complete. The formation of the nanostructures is primarily due to the existence of rich trace elements in the rice bran. The importance of these trace elements and the formation of AlN nanotowers/nanorods have been discussed with the VLS/VS growth mechanisms. The unique morphology of the as-synthesized nanotowers could be useful for investigating fundamental physical phenomena and for fabricating nanodevices.