Nanocrystalline Aluminum Nitride and Aluminum/Gallium Nitride Nanocomposites via Transamination of [M(NMe2)3]2, M = Al, Al/Ga (1/1)

Abstract

Reactions of [Al(NMe2)3]2 with NH3, mimicking the case of the related Ga-derivative, provided an Al−amide−imide precursor that was pyrolyzed to pure nanocrystalline AlN. Based on that chemistry, a mixed Al/Ga precursor system was designed to lead to the bimetallic nitride composites. A prototype study included equilibration in hexane or toluene of the dimers [M(NMe2)3]2, M = Al, Ga, which resulted in the formation of the homoleptic four-membered-ring compound (Me2N)2Al(μ-NMe2)2Ga(NMe2)2. Crystalline [M(NMe2)3]2, M = Al/Ga (1/1), obtained from this equilibration was structurally characterized. Transamination/deamination reactions carried out with liquid NH3 in the preequilibrated bimetallic system [Al(NMe2)3]2/[Ga(NMe2)3]2, Al/Ga = 1/1, resulted in the mixed M−amide−imide precursors that were converted at 700−1100 °C to aluminum/gallium nitride nanocomposite materials. The nature of these bulk nanocomposites has been elucidated by XRD, TEM/EDS, IR, and PL techniques.