Morphology-controlled synthesis of quasi-aligned AlN nanowhiskers by combustion method: Effect of NH4Cl additive

Uniform quasi-aligned AlN nanowhiskers grown in the reacting Al particles have been successfully prepared in high content by combustion synthesis using NH₄Cl as a morphology-controlled promoting additive. FE-SEM and TEM images show that the nanowhiskers, which are single-crystalline hexagonal wurtzite AlN growing along [0 0 1] direction, have diameters in the range of 80–170 nm and a length of several to several tens of micrometers. The effect of NH₄Cl on the growth of nanowhiskers was discussed. It was found that NH₄Cl not only controlled the products’ morphology, but also changed the combustion behavior and nitridation mechanism in the combustion synthesis process.