Synthesis and characterization of AlN whiskers by nitridation of Al4O4C

A novel route has been developed to synthesise AlN whiskers by heat-treating Al4O4C via Si atom doping under a nitrogen atmosphere. The resulting AlN whiskers have dimensions of greater than 200 nm in diameter and several hundred microns in length, and the whiskers, with their zig-zag shaped, noodle-like morphology, were formed by adjusting the heat-treatment conditions. TEM observation indicates that these whiskers are mono-crystalline and grow along the [001] direction. Possible reaction mechanisms responsible for the formation of these AlN whiskers were discussed. In addition, N2 can accelerate the decomposition of Al4O4C, which provides meaningful information for the application of Al4O4C under a nitrogen atmosphere at high temperatures.