Synthesis of novel mesoporous Al2O3 microspheres with flower-like structure

Using glucose as a structuring additive and aluminium nitrate as the Al precursor, a novel kind of mesoporous Al2O3 microspheres with flower-like structure were synthesized hydrothermally at 180A degrees C for 20 h. When the synthesis temperature was lowered to 140A degrees C, the carambola-like Al2O3 can be synthesized. This approach is convenient and simple, and flower-like Ce-Al2O3 and La-Al2O3 spheres have also been prepared in this way. It may be applied to synthesize other metal oxides when suitable precursor salts are used. From an analysis of the experimental results, a mechanism for the formation of the flower-like Al2O3 spheres has been proposed and discussed.