The ordered mesoporous silicas containing transition metals are versatile catalytic materials for oxidation of a wide range of organic compounds. In order to obtain active catalysts, different active redox metal sites have been introduced into specific locations (mesoporous channels and framework) of ordered mesoporous silicas (OMSs). All the reported results evidenced that localization of metal ions, their interaction with another metal (bimetallic catalysts) and the support, with typical properties of the ordered mesoporous silica, influenced the oxidation state, respectively their redox properties. To support this, the results regarding the specific properties of transitional metals in the ordered structure of silica, obtained using various characterization methods, were presented. The activity of metal sites in the oxidation reactions was evidenced in various applications carried out in the liquid or gaseous phase. The oxidation of various organic compounds in liquid phase with H2O2 (especially aromatic compounds and of alcohols) and in gas phase with oxygen from air was presented for a variety of metal-modified OMSs. The active sites and possible reaction mechanisms were presented for some catalytic systems. The immobilization of multiple metal active species on new ordered porous frameworks and their synergistic interactions remain topics of interest in the future.
Part of the book: Redox