Iron-Cobalt-Silica nanocomposites were prepared in form of aerogels. X-ray diffraction, transmission electron microscopy and N-2 physisorption at 77 K were used to investigate the structure, size and dispersion of the nanocrystals and the porous structure in the aerogels and in the final composites. The variation of the supercritical drying conditions gives rise to differences in the morphological features of the aerogels. These differences influence the size of the cobalt oxide nanoparticles in the aerogels. On the other hand, after the reduction treatment the average size of the alloy nanoparticles is the same in all the aerogel nanocomposites. The effect of reduction temperature on alloy formation and particle size is also discussed.
Iron-Cobalt-Silica aerogel nanocomposite materials
CASULA, MARIA FRANCESCA;CORRIAS, ANNA;
2003-01-01
Abstract
Iron-Cobalt-Silica nanocomposites were prepared in form of aerogels. X-ray diffraction, transmission electron microscopy and N-2 physisorption at 77 K were used to investigate the structure, size and dispersion of the nanocrystals and the porous structure in the aerogels and in the final composites. The variation of the supercritical drying conditions gives rise to differences in the morphological features of the aerogels. These differences influence the size of the cobalt oxide nanoparticles in the aerogels. On the other hand, after the reduction treatment the average size of the alloy nanoparticles is the same in all the aerogel nanocomposites. The effect of reduction temperature on alloy formation and particle size is also discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.