Aluminum nitride (AlN) nanocrystals were successfully synthesized from the reaction of AlCl₃ and Mg₃N₂ at the temperature of 500 ℃ using simple equipments. The XRD and XPS show that the obtained samples are pure hexagonal AlN and the level of impurity in the samples is lower than the resolution limit of the spectrometers. The TEM image shows that the shape of the AlN samples is reticular, and the size of the skeleton of the reticular structure is about 10～20 nm. The optical properties of the AlN samples were also investigated. The results show that its band-gap value is 6.12 eV, there is an intensive and board band centered at 680 cm^－1 in its FT-IR spectrum and its Raman frequencies are lower than that of AlN films and AlN single crystals.

Key words: nano-aluminum nitride, synthesis, optical property