Synthesis, characterization, and growth mechanism of α-Cr2O3 monodispersed particles

Monodispersed spherical particles of chromium (III) oxide, alpha-Cr2O3, were successfully synthesized from a diluted solution of KCr(SO4)(2)center dot 12H(2)O using the Aqueous Chemical Growth (ACG) technique. The spherical alpha-Cr2O3 particles obtained were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and Raman spectroscopy for structural, surface morphological, chemical, and physical properties, as a function of deposition time. The XRD and Raman spectroscopy showed that aging had no apparent effect on the structure of the obtained uniform fine (in the range of micron-nano-level)-spherical particles of alpha-Cr2O3. The use of SEM demonstrated that aging had a clear influence on the size and the particles size distribution. Accordingly, the time dependence of the average diameter of alpha-Cr2O3 spherical particles follows the d(3) law as required for diffusion-limited Ostwald ripening. (C) 2011 Elsevier Ltd. All rights reserved.