Properties of nanostructured GaN prepared by different methods

Various methods have been employed to prepare nanostructured GaN exhibiting reasonable surface areas. The methods include ammonolysis of γ-Ga2O3 or Ga2O3 prepared in the presence of a surfactant, and the reaction of a mixture of Ga2O3 and Ga(acac)3 with NH3. The latter reaction was also carried out in the presence of H3BO3. All the methods yield good GaN samples as characterized by X-ray diffraction, electron microscopy and photoluminescence measurements. Relatively high surface areas were obtained with the GaN samples prepared by the ammonolysis of γ-Ga2O3 (53 m2 g−1), and of Ga2O3 prepared in the presence of a surfactant (66 m2 g−1). GaN obtained by the reaction of NH3 with a mixture of Ga2O3, Ga(acac)3 and boric acid gave a surface area of 59 m2 g−1. GaN nanoparticles prepared by the nitridation of mesoporous Ga2O3 samples generally retain some porosity.