Synthesis of spherical SBA-15 mesoporous silica. Influence of reaction conditions on the structural order and stability

The structural order and stability of spherical SBA-15 silicas synthesized under acid conditions were evaluated as a function of surfactant Pluronic 123 (P123), tetraethyl orthosilicate (TEOS), and hydrochloric acid (HCl) concentrations in the initial gel composition. Also, the effect of temperature and reaction time was studied. Samples were characterized by small angle X-ray diffraction (SAXS), nitrogen adsorption desorption analyses, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that synthesis conditions affect the structural order and stability of the SBA-15 silicas. These silicas exhibited an ordered pore structure and regular spherical morphology with size from 2 to 5 p.m. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.