Synthesis of Mesoporous Silica Submicrospheres with High Specific Surface Area via a Modified Octylamine Templating Process

Abstract

Mesoporous silica submicrospheres with high specific surface area, 930.9m⁹/g, were synthesized without using any acid or alkali as catalyst. Tetraethoxysilane as silica source, octylamine as template and polyoxyethylene (20) sorbitan monolaurate as emulsifier were adopted in this work. The as-prepared spheres were characterized with scanning electron microscopy, energy disperse spectroscopy, thermal gravimetric analysis, small angle X-ray diffraction and nitrogen adsorption, respectively. The results showed that octylamine vesicles were incorporated by silica shell in dilute sodium chloride solution, and the morphology and dispersity of submicrospheres were improved by using polyoxyethylene (20) sorbitan monolaurate. Moreover, the size of as-prepared products was gradually decreased as the amounts of polyoxyethylene (20) sorbitan monolaurate increased. In addition, the shell of the submicrospheres with narrowly distributed nanopores became more and more unordered with the prolonging of the calcinating time.