Synthesis of mesoporous amorphous MnO2 from SBA-15 via surface modification and ultrasonic waves

Ultrasonic waves in combination with nanocasting method have been successfully used in preparation of mesoporous amorphous MnO2 from SBA-15. Modification of the intrachannel surfaces of SBA-15 with amino making them hydrophilic ensures precursor KMnO4 to readily penetrate the pore channels. Moreover, the modification changes the surface reactivity, enabling the formation of MnO, inside the pores of SBA-15 by the sonochemical reduction of metal ions. The texture/structures of the resultant materials were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), Fourier transform-infrared (FT-IR) spectroscopy, Raman scattering and nitrogen adsorption/desorption measurements. The loading percentage can be controlled via sonochemical time and almost 76% of the mesoporous volume of the SBA-15 host was finally occupied by nanoparticles MnO2. The novelty of presented approach is 2-fold: a new synthetic concept - a simple and effective method to allow practically a high filling of the pores for fabricating mesoporous metal oxide; and the morphology of the resultant is easier to control, for the formation of metal oxide was completed during the sonochemical process instead of during heat treatment. (c) 2006 Elsevier Inc. All rights reserved.