Design of SiO2 materials with hierarchical structure as promising supports for catalysts

Abstract

Abstract The silicate support with a hierarchical structure based on diatomite and MCM-41 is synthesized. The MCM-41 is formed directly on the surface of diatomite and from the diatomite itself without the use of additional silica precursors. The structure of the synthesized samples is characterized by the low-temperature nitrogen adsorption and scanning electron microscopy (SEM). It was shown that hydrothermal treatment of diatomite with NaOH and cetyltrimethylammonia bromide leads to the partial dissolving of diatomite with self-assembly of MCM-41 fragments inside diatomite pores. The developed approach has demonstrated the opportunity to obtain the supports based on diatomite and MCM-41 that are characterized by a hierarchical structure (macropores of diatomite with size of 10-500 nm and mesopores of MCM-41 with size of 3-4 nm) and a high specific surface area that is promising for their application as supports for catalysts.