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In the present study, MgFe2O4 nanofibers with smaller diameter have been successfully fabricated via electrospinning utilizing sol–gel precursor. The single phase of spinel ferrite was obtained at 700 °C. Different PVP concentrations were used and the results show that PVP concentration had played important role in the formation, uniformity, homogeneity and particularly in the reduction of nanofibers diameter. The average diameter of the nanofibers prepared with PVP concentration (6.3, 7.6, and 8.9 wt%) and calcined at 700 °C were 70 ± 7.6, 86 ± 11 and 113 ± 13 nm respectively.

The effect of alumina precursor on the synthesis of nanosized LaAlO3 powders by reverse micelle process has been studied. The synthesized and calcined powders were characterized by thermogravimetry-differential thermal analysis, X-ray diffraction analysis and transmission electron microscopy. Differential thermal analysis showed that LaAlO3 phase transformation occurs at 830 °C and 866 °C for Al(NO3)3 and AlCl3 precursor respectively. With Al(NO3)3 as starting precursor, well-crystallized LaAlO3 phase was formed at lower temperature. Use of AlCl3 as precursor resulted in bigger particle formation (∼41 nm) while Al(NO3)3 forms much smaller particles (∼28 nm) as confirmed by transmission electron microscopy.

Alumina-zirconia composite powders were produced by sol-gel autocombustion. 20 wt.% ZrO2-Al2O3 mixture precursor solutions were chelated by citric acid ions at different pH. DTA analysis shows sluggish decomposition at low pH, whereas there was rapid decomposition at high pH = 9. XRD patterns of the calcined powders showed that well crystallized powder with 100 % tetragonal phase and α-alumina phase is produced when pH = 0.58 (without ammonia addition). TEM characterization of composite powders revealed homogenous distribution of nanosized zirconia particles in the alumina matrix. FTIR analysis shows peaks at 590 cm−1 and 454 cm−1, which are identified as the characteristic absorption bands of Zr-O and Al-O.