Stepwise conversion of a single source precursor into crystalline AlN by transamination reaction

Ammonolysis of the monomeric, base-stabilized trisaminoalane Me3N-Al[N(H)Dipp)]3 (Dipp=2,6-iPr2–C6H3) yielded Al–N oligomers, which were characterized in detail by solid state NMR spectroscopy (1H, 13C, 15N, 27Al) and TGA/DTA. Pyrolysis of as-prepared oligomers at different temperatures in an argon steam yielded carbon-containing black solids, whereas pyrolysis under a steady flow of NH3 produced pure aluminum nitride (AlN). The role of the pyrolysis temperature and the influence of NH3 on the formation of crystalline materials were investigated. As-prepared AlN was characterized by solid state NMR spectroscopy (15N, 27Al), X-ray diffraction (XRD), transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS). Theoretical calculations were performed in order to identify potential reaction intermediates.

Graphical abstractAmmonolysis reactions of Me3N–Al(NHDipp)3 in liquid NH3 yielded Al–N oligomers, which can be transformed into nanocrystalline aluminum nitride particles under thermolysis conditions at 1000 °C. Theoretical calculations were performed in order to identify potential reaction intermediates.Figure optionsDownload full-size imageDownload as PowerPoint slide