Nano-sized alumina is prepared using a cost-effective solvent-free method with aluminum nitrate and ammonium bicarbonate precursors. Combined investigations by thermal analysis (TG/DTA), X-ray diffraction (XRD), specific surface area (BET), scanning electronic microscopy (SEM), infrared emission spectroscopy (FTIR), dynamic light scattering (DLS) and dilatometry were used to examine the effects of calcination temperature on the formation of Al 2 O 3 . XRD analysis shows that the γ-Al 2 O 3 phase forms already at 300 °C and slowly continues to form with increasing temperature indicating a diffusion-controlled reaction as shown by FTIR. The size of the γ-Al 2 O 3 nanocrystalline, as determined by XRD, is between 1.5 and 1.9 nm and slowly increased with the reaction temperature. DLS results revealed that a particle size of γ-Al 2 O 3 dispersed in water grows with increasing reaction temperature due to nanocrystalline particle aggregation, which was additionally confirmed by SEM. The densification behavior of the boehmite and γ-Al 2 O 3 phases was investigated using dilatometry.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Industrial and Manufacturing Engineering
- Materials Chemistry