Pyrolytic conversion of the cage-type precursors into AlN

Aluminum nitride (AlN) was prepared via pyrolysis of cage-type poly(alkyliminoalane) [(HAlNR), (R=Et, ⁱPr)] under Ar or NH₃-N₂ atmospheres. Both (HAlNⁱPr), and (HAlNEt)_m were converted into ceramic residues with relatively high ceramic yields. The ceramic residues obtained via pyrolysis of the precursors under an Ar atmosphere contained considerable amounts of carbon, while most of carbon was removed during the pyrolysis under an NH₃-N₂ atmosphere. The only obtained crystalline phase was AlN, whose lattice parameters showed that isostructural Al₂OC was rarely dissolved in the lattices of the 2H wurtzite-type structures.