Evidence for the presence of Mo(VI), W(VI) or Re(VII) species in silica-based materials. New approaches to highly dispersed oxo-species in mesoporous silicates

Abstract

d ⁰ Transition metal-containing mesoporous molecular sieves are synthesized by the hydrolysis of tetraethyl orthosilicate in aqueous acid, in the presence of neutral or anionic low-condensed Mo(VI) or W(VI) oxo–peroxo or Re(VII) polyoxo species and a cationic surfactant; the materials have a nearly homogeneous distribution of the dopants and promising catalytic activities.