GROWTH OF NANO-ALPHA-FE2O3 IN A TITANIA MATRIX BY THE SOL-GEL ROUTE

Nano-alpha-Fe2O3 in a titania matrix was prepared by the sol gel route . The nanocomposites containing various sizes of alpha-Fe2O3 were prec ipitated by the heat treatment of the dried gel in a temperature range 100 1200 degrees C. Differential thermal analysis of the TiO2 Fe2O3 s ystem showed peaks at 325, 390 and 730 degrees C. The formation of ana tase as well as the rutile phase of TiO2 and the growth of alpha-Fe2O3 were predicted from the above peak analysis. These results were in ag reement with the X-ray diffraction studies. The sizes of the nanoparti cles were analysed by transmission electron microscopic studies. The M ossbauer spectra of TiO2 Fe2O3 nanocomposites showed paramagnetic and superparamagnetic doublets for all the specimens containing nanopartic les of alpha-Fe2O3. The electron paramagnetic resonance study indicate d the presence of a paramagnetic phase in the nanocomposite samples. ( C) 1998 Chapman & Hall.