Synthesis of high surface area Al2O3–CeO2 composite nanopowder via inverse co-precipitation method

In the present work, Al2O3–CeO2 composite nanopowder was synthesized by inverse co-precipitation method using metal chlorides, aluminum powder and NH4OH as precipitant agent. The thermal decomposition of the precipitate and subsequent formation of Al2O3–CeO2 were investigated by X-ray diffractometery, scanning electron microscopy, thermogravimetric and differential thermal analysis, Brunauer–Emmett–Teller surface area measurement and Fourier transform infrared spectroscopy. The results showed that the presence of ceria suppressed the formation of α-Al2O3. The BET-specific surface area was 173 m2/g for powders calcined at 800 °C. The particle size examined by using scanning electron microscopy was in the range 30–70 nm. The activation energy of Al2O3–15 wt.% CeO2 nanocrystallite growth during calcination was measured to be 32.4 kJ/mol whereas that of Al2O3 was about 23.8 kJ/mol.