Surface functionalization of SBA-15 by the solvent-free method

Fabrication of Metal Oxides Occluded in Ordered Mesoporous Hosts via a Solid‐State Grinding Route: The Influence of Host–Guest Interactions

“…Contrastingly, all of the guest molecules were well dispersed on S373C, the bare SBA-15 sample calcined at 373 K, under the conditions depicted in Figure 3, which will be discussed in detail later. Combined with previous results from our group, [23] it can be considered that the surface silanol density played the key role in this solid-state grinding method. More silanol groups in mesoporous silica may favor the enhancement of host-guest interactions and, thus, lead to a high dispersion level of the guest species.…”

“…[22] The enhanced interaction between the guest and the host in solid-state inclusion obviously favors a high dispersion of the guest species on the mesoporous host; consequently, copper oxides and ferric oxides, as well as other metal oxides, can be highly dispersed on SBA-15 by the solid-state grinding method. [23] As pure silica mesoporous supports have no geometric confinement or cationic sites, but do contain surface silanols, the reservation of more silanols within the channels seems to be one useful method of enhancing the guest-host interaction, which favors the formation of highly dispersed surface species.…”

“…These results validate the distinctive role played by surface silanol groups in the functionalization of mesoporous silica with metal oxides, in which fewer surface silanol groups will favor the formation of M-O-M species on the composites. [23] …”

Direct synthesis of highly ordered Fe-SBA-15 mesoporous materials under weak acidic conditions

“…However they didnÕt give detailed studies on the direct hydrothermal synthesis of the Fe-SBA-15 materials [17]. There are also reports about SBA-15 supported iron oxides catalysts prepared by impregnation or grinding methods [27][28][29][30]. Nevertheless, the grafting and impregnation methods are not suitable to prepared catalysts with highly isolated catalytic active sites and the metal oxides tend to appear in the channel or external surface of the products as byproducts which would jam the channels or play a negative role in catalysis [31].…”

Preparation and characterization of vanadium(IV) oxide supported on SBA-15 and its catalytic performance in benzene hydroxylation to phenol using molecular oxygen

“…This absorption became more intensive with the increasing of hydrothermal time, indicating the increasing of V(IV)O x species. to the combination and overtone bands mainly from the surface silanol groups [44]. These bands remarkably weakened with increase in hydrothermal time, indicating the reaction of the surface silanol groups on SBA-15.…”