Synthesis and characterization of Al2O3 hollow spheres

This paper presents a novel technique to create Al₂O₃ hollow spherical nanoparticles. It used Al(OH)₃ which was synthesized with Al₂(SO₄)₃ and NaOH, and the C-Al(OH)₃ core-shell nanoparticle as intermediate phases. The Al₂O₃ hollow spheres were achieved by the calcination of the carbon cores and the dehydration of Al(OH)₃. The chemical composition, morphology, size and superficial crystal structure of the nanoparticles were characterized with TEM, XRD, TGA, FTIR and BET. The result shows that the average diameter of the C-Al(OH)₃ core-shell nanoparticles is about 25 nm, the thickness of the Al₂O₃ shell is about 5 nm and the surface area is 215.2 m²/g. The procedure for the formation of Al₂O₃ hollow nanoparticles is discussed in details.