Different routes to the pore engineering of spherical MCM-41

Abstract

Different routes, including the replacements of the template, addition of pore expander and hydrothermal post-synthesis treatment have been used for the pore engineering of spherical MCM-41. A comparison among the pore engineering effects of these methods has been made. The results show that the hydrothermal post-synthesis treatment affords the synthesized material with a larger pore size and narrow pore size distribution without changing the spherical morphology. As far as the pore-size expansion is concerned, the addition of DMTA is the most effective one, but this might be limited by the spherical, morphology. Combining the replacement of C₁₆ TMABr with the Gemini surfactant GEM 16-8-16 with an addition of DMTA gives rise to the largest pore volume and surface area.

Keywords

spherical MCM-41 / pore engineering / pore expander / post-synthesis treatment / Gemini surfactant

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