Mesoporous material formed by acidic hydrothermal assembly of silicalite-1 precursor nanoparticles in the absence of meso-templates

Abstract

Silicalite-1 precursor nanoparticle solutions are prepared from a mixture of TPAOH, H 2O and TEOS. Acidification of the clear nanoparticle solution and a consequent hydrothermal treatment results in the formation of a large pore mesoporous material. The use of meso-templates for the formation of the mesopores is no longer required. These materials will be denoted mesosil. The porous characteristics of mesosil materials can be adjusted by controlling synthesis time, temperature and pH. The maximum surface area and pore volume are up to 600 m 2/g and 1.35 cm 3/g, respectively. The porosity in these materials originates from the interparticle voids between the nanoparticles (size approximately 5 nm) in contrast to the framework porosity of M41S, SBA-15, and similar materials in which mesopores are formed through a templated synthesis route. The material is characterized by N 2-sorption, TEM, FT-Raman, DRIFT and TGA measurements.