Influence of synthesis conditions on morphological features of the SBA-15 containing only elongated and rounded/spherical grains

Abstract

Mesoporous silica SBA-15 materials of high specific surface area (~700 m2 g−1) were synthesized by using block copolymer Pluronic P123 as template and tetraethoxysilane as silica source. The obtained materials were characterized by XRD, nitrogen adsorption - desorption measurements, SEM, EDS and AFM analysis. It was found that small modifications of synthesis conditions influenced the morphological features of the synthesized SBA-15 samples. The SEM analysis had shown that the SBA-15 synthesized at lower temperature and longer time of reaction (80°C, 48 h) provided elongated rod-shaped grains about 1μm long. The other sample synthesized at higher temperature and shorter time of reaction (100 °C, 24 h) had rounded grains and grains of regular spherical shape with diameters ranging from 0.5 to 2 μm. The EDS analysis confirmed that the particles of both synthesized samples were of the SiO2 content. In addition, the AFM analysis had shown different surface morphologies of the materials synthesized under various conditions. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III-45012, Grant no. III-45005 and Grant no. OI-172045]

Keywords

• mesoporous material
• SBA-15
• synthesis conditions
• nanostructures
• spherical grains