Wet chemical methods of manufacturing alumina nanopowders
|Aleksandra E. Kędzierska 1,3, Jerzy Morgiel 2, Waldemar Pyda 3|
1. Institute of High Pressure Physics, Warsaw 01-142, Poland
Four wet chemical methods of manufacturing isometric nanoparticles of corundum was compared. This was: calcination of as-recived precipitate, calcination of hydrothermaly crystallized precursor, the citrate-nitrate method and calcination of AACH precursor - AACH method. In the first three methods the starting material was aluminum nitrate, in fourth method it was aluminum ammonium sulfate from which was precipitated AACH (aluminum ammonium carbonate hydroxide). Powders were crystallized at temperatures which limited corundum crystallites growth and maximize participation of alpha-Al2O3 phase. Intensive milling was used during calcination as well as the end of calcination. The DSC/TG method was used to characterize precursors of alumina oxide during calcination. Phase composition and specific surface area were determined by X-ray diffraction and BET methods, according to method of manufacturing and temperature of calcination. Particle size distribution was designated by laser method (DLS) and morphology of obtained powders was observed by Transmission Electron Microscopy (TEM). It was found that the milling precursors operation decreased the temperature of crystallizing alpha-phase. Crystallites shape which was closest to the spherical was obtained using the citrate-nitrate and AACH method.
Presentation: Poster at Warsaw and Karlsruhe Nanotechnology Day, by Aleksandra E. Kędzierska
See On-line Journal of Warsaw and Karlsruhe Nanotechnology Day
Submitted: 2011-09-15 17:09 Revised: 2011-09-15 17:09