Aluminum nitride nanobelts with hexagonal structure were successfully synthesized by evaporating aluminum powder in ammonia/nitrogen atmosphere at 1200℃. The as-prepared AlN nanobelts have a rectangular cross section with a width of 30-500nm and length of about 100m. The optical characterization indicates that the vibration modes of the AlN nanobelt agree well with those of AlN film despite its nanobelt geometry. This nanobelt geometry of AlN could be important for the construction of GaN-based nanoheterostructures in future nanoelectronics.

Aluminum nitride nanostructures are attractive for many promising applications in semiconductor nanotechnology. Herein we report on vapor-solid growth of quasi-aligned aluminum nitride nanocones on catalyst-coated wafers via the reactions between AlCl3 vapor and NH3 gas under moderate temperatures around 700℃, and the growth mechanism is briefly discussed. The as-prepared wurtzite aluminum nitride nanocones grow preferentially along the c-axis with adjustable dimensions of the sharp tips in the range of 20-60nm. The photoluminescence spectrum reveals a broad blue emission band with a fine photon structure while the field emission study shows a notable emission current with a moderate turn-on field as expected, suggesting their potential applications in light and electron emission nanodevices.

By using the in situ thermal analysis-mass spectroscopic technique, combined with transmission electron microscopic characterization of the carbon nanotube (CNT) product, we have studied the chemical vapor deposition (CVD) growth of CNTs with Fe-Co/Á-Al2O3 catalyst and benzene precursor in the range of room temperature to 700℃. The growth process has been clearly illuminated, which starts from the reduction of catalyst around 645℃ followed by the dissociation of carbon-hydrogen bonds of benzene and the sequential growth of CNTs. A surprising fact is that no possible hydrocarbon species derived from benzene was detected, indicating that the carbon-carbon bond was not broken under our experimental conditions. All of the experimental results strongly reinforce the six-membered-ring-based growth model, and a schematic elucidation is presented accordingly. This in situ study not only reveals the unique and convincing information directly related to the growth mechanism from the involved chemistry, but also provides a powerful way to clarify the mechanism of CVD synthesis of CNTs with other precursors.