Structural, surface and optical properties of nanoalumina produced by various ways

Abstract

Start The compared study of the properties of liquid-phase and electric explosion alumina nanoparticles was made. The X-ray diffraction analysis demonstrated that these nanoparticles remain in amorphous and semi-amorphous states. The complete structural information of Al2O3 nanoparticles was obtained as a result of the full-profile refinement of their model phase parameters. The parameters of the unit cells, spatial distribution of atoms, and occupancy of nodes were also determined.The data of IR spectra of surface OH groups and adsorbed CO revealed that the surface imperfection of an electric explosive sample is lower than that obtained using the liquid-phase method. Using photoluminescent spectroscopy, impurities of Cr3+, Mn4+ and Ti3+ in the octahedral oxygen coordination and Fe3+ in the tetrahedral oxygen coordination were detected. It was observed that the concentration of these impurities was significantly higher in the electric explosion sample. Using UV-Vis DR spectroscopy, it was found that the liquid-phase sample was amorphous, and the electric explosive sample was well crystallized and most probably consisted of 2D and 3D nanostructures.