There are several methods to synthesize nanostructured alumina, each with its own advantages and limitations:
1. Sol-Gel Method: This involves the hydrolysis and condensation of aluminum alkoxides, resulting in a gel that can be dried and calcined to produce nanostructured alumina.
2. Hydrothermal Synthesis: This method uses high-pressure and high-temperature conditions to crystallize alumina nanoparticles from aqueous solutions.
3. Mechanical Milling: Here, bulk alumina is mechanically ground to nanoscale dimensions, often combined with other processes like annealing to achieve the desired properties.
4. Template-Assisted Methods: These involve using templates such as porous anodic alumina to guide the formation of nanostructured alumina.
