H2SO4-assisted hydrothermal preparation of γ-AlOOH nanorods

A facile hydrothermal method was developed to synthesize gamma-AlOOH nanorods using AlCl3 and NH4OH as the reactants and H2SO4 as the morphology-directing agent. Amorphous Al(OH)(3) was formed by mixing AlCl3 and NH4OH solutions at room temperature and then the hydrothermal treatment of the amorphous Al(OH)(3) in dilute H2SO4 solutions at 240 degrees C for 16.0 h led to the formation of gamma-AlOOH nanorods with a preferential growth along [100] direction. The structure, morphology, size of the products were investigated by powder X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED). Our experiments showed that the increase of H2SO4/Al(OH)(3) molar ratio from 0 to 0.05 was favorable for the formation of gamma-AlOOH nanorods with high aspect ratio (about 80). (C) 2008 Elsevier B.V. All rights reserved.