Structure Analysis of Nanocrystalline MgO Aerogel Prepared by Sol-Gel MethodSolid State Phenom. (2007)
Wet gel obtained by sol-gel technique was dried in supercritical CO2 to prepare hydrated form of magnesium oxide. Calcination at 723 K under vacuum yielded nanocrystalline MgO aerogel. Structure studies were performed by X-ray diffraction, scanning and transmission electron microcopies. Electron microscopy images reveal rough, unfolded and ramified structure of solid skeleton. Specific surface area SBET was equal to 238 m2/g. X-ray pattern reveals the broadened diffraction lines of periclase, the only crystalline form of magnesium oxide. The gamma crystallite size distribution was determined using FW 1/5/4/5 M method proposed by R. Pielaszek. The obtained values of and ó (measure of polydispersity) of particle size parameters are equal to 6.5 nm and 1.8 nm, respectively, whereas the average crystallite size estimated by Williamson-Hall procedure was equal to 6.0 nm. The obtained at Rietveld refinement Rwp, and S fitting parameters equal to 6.62% and 1.77, respectively, seem to be satisfactory due to the nanosize of MgO crystallites and because of the presence of amorphous phase.
Citation InformationG. Dercz, L. Pajak, K. Prusik, R Pielaszek, J.J. Malinowski, W. Pudlo, "Structure Analysis of Nanocrystalline MgO Aerogel Prepared by Sol-Gel Method" Solid State Phenom. 130 (2007): 203-206.