Synthesis and characterization of gallium nitride nanoparticles by using solvothermal-soft-chemical methodology

GaN nanoparticles have been synthesized by solvothermal method. Gallium acetyl-acetonate and ammonium acetate were mixed in stoichiometry conditions. The reaction was induced in different solvents such as ethanol, ethylene glycol, propanol and benzene. The as-prepared materials were heat-treated from 240 to 950 °C. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) put in evidence that the resulting intrinsic-structure is highly linked with the solvent in turn and with temperature. It was found that wurzite phase is reached at 950 °C with benzene as a solvent; with surface area of 50 m² g^-1, measured by nitrogen physisorption. In addition, well-defined GaN-nanoparticles were determined using SEM-EDS and HRTEM for a diffraction-selected area (SAED). Moreover, optical properties obtained by using photoluminescence (PL) spectroscopy indicated a well crystal-definition from bands at 2.85 and 3.0 eV related with structural defects. GaN deposited onto an ITO substrate induced a more cathodic current corresponding to hydrogen evolution compared with ITO free of GaN in neutral conditions.