Morphologies of Al_2O_3 shell prepared from Al/A100H-nH_2O core-shell particles

摘要

Influence of calcination temperature on the morphologies of Al_2O_3 shell with ~2 mu m in diameter and ~200 nm in wall thickness, which were prepared via the calcination of the Al/AlOOH-nH_2O core-shell particles, was investigated. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), SAED, and N_2 adsorption-desorption isotherms were used to characterize the as-prepared samples. The experimental results indicated that the intact Al_2O_3 shells were composed of nanorods-like particles when calcined at 900 deg C, and increasing temperature lead to the evident growth of these nanoscale particles, with the surface morphology of Al_2O_3 shell variety from rough to smooth configuration. N_2 adsorption results revealed the specific surface area decreased from 114 m/g for shells obtained at 900 deg C to 40 m~2/g for that obtained at 1100 deg C. and the hollow sphere with porous shell provides the possibilities in the applications for catalyst and medical carriers due to its high specific surface area.