Keggin based self-assembled mesoporous materials for the capture of selective guest molecules

Abstract

A series of self-assembled mesoporous materials, compounds 1–9, of the type [RPPh₃]_n[XM₁₂O₄₀] (R = Ph, Me, Et; n = 3 or 4; X = P, Si; M = Mo, W) composed of Keggin anions and phosphonium cations have been fabricated and characterized. These thermally stable hybrid materials show selective reversible uptake of non-polar molecules such as iodine and carbon disulfide under ambient conditions. The resultant porosity is attributed to the self-assembling of the cations on the surface of the Keggin anion such that the pores are lined with the phosphonium cations rendering them hydrophobhic. The present work explores the spontaneous self-assembly process of POM integrated mesoporous compounds stabilized via non-covalent interactions and their potential applications as adsorbing materials.