A Review: Fundamental Aspects of Silicate Mesoporous Materials

TLDR

Silicate mesoporous materials are prized for their high surface areas and large, uniform pores (2–10 nm), surpassing microporous zeolites and enabling applications in catalysis, separation, adsorption, functional materials, and guest confinement. This review provides a concise overview of silicate mesoporous materials and their applications, giving researchers succinct information on both microporous and mesoporous systems. They are synthesized by employing long‑chain surfactants as structure‑directing agents, with their structure, composition, and pore size tunable through reactant stoichiometry, surfactant choice, auxiliary chemicals, reaction conditions, or post‑synthesis functionalization.

Abstract

Silicate mesoporous materials have received widespread interest because of their potential applications as supports for catalysis, separation, selective adsorption, novel functional materials, and use as hosts to confine guest molecules, due to their extremely high surface areas combined with large and uniform pore sizes. Over time a constant demand has developed for larger pores with well-defined pore structures. Silicate materials, with well-defined pore sizes of about 2.0–10.0 nm, surpass the pore-size constraint (<2.0 nm) of microporous zeolites. They also possess extremely high surface areas (>700 m2 g−1) and narrow pore size distributions. Instead of using small organic molecules as templating compounds, as in the case of zeolites, long chain surfactant molecules were employed as the structure-directing agent during the synthesis of these highly ordered materials. The structure, composition, and pore size of these materials can be tailored during synthesis by variation of the reactant stoichiometry, the nature of the surfactant molecule, the auxiliary chemicals, the reaction conditions, or by post-synthesis functionalization techniques. This review focuses mainly on a concise overview of silicate mesoporous materials together with their applications. Perusal of the review will enable researchers to obtain succinct information about microporous and mesoporous materials.