Concentration of surface hydroxyl groups on MCM-41

PMo or PW heteropoly acids supported on MCM-41 silica nanoparticles: Characterisation and FT-IR study of the adsorption of 2-butanol

“…6A and B) in agreement with results previously reported by other authors [47,48]. These bands are assigned to adsorption on weak Lewis-type acid sites or to weakly hydrogen-bonded pyridine.…”

“…9a) show bands at 3740 and 3550 (shoulder) cm À1 corresponding to the n(OH) vibration mode of the silanol groups (SiOH) inside the channels without and with strong hydrogen-bonding interaction, respectively [47,48]. The intense and broad band below 1350 cm À1 is assigned to Si-O stretching modes.…”

Synthesis and magnetic characterization of magnetite particles embedded in mesoporous MCM-41

“…Because the inner walls of the MCM-41 channels are irregularly coated with isolated surface silanol groups [17], hydrophobic and hydrophilic areas exist within the channels. Hence, when an inorganic iron salt in a polar solvent is used at the impregnation step, an heterogeneous distribution of the iron product is obtained in the final composite [7,8].…”

MCM-41 prepared with ionic liquid and cethytrimethylammonium bromide as co-templates

“…MCM-41 were synthesized with different molar ratio of RTIL to CTAB, and the characterization of the products were determined by XRD [13] and ASAP 2000 automatic physics adsorption instrument, respectively.…”