High yield synthesis and characterization of well-ordered Mesoporous silica nanoparticles using Sodium Carboxy Methyl Cellulose

In the present work, mesoporous silica nanoparticles (MSNs) with well-ordered hexagonal structure were synthesized using Sodium Carboxy Methyl Cellulose. The MSNs were characterized by scanning electron microscopy, dynamic light scattering, powder XRD, nitrogen physisorption and Transmission electron microscopy. The MSNs were also functionalized with thiol groups and its capacity toward adsorption of a large cation, i.e. lead was investigated. Scanning electron microscopy reveals that MSNs have semi-spherical shapes. The XRD pattern of the calcined sample shows at least five well-defined peaks which point out that silicate nanoparticles have hexagonal array of pores as MCM-41 structure. The nitrogen adsorption isotherm displays a type IV isotherm according to the IUPAC classification. A sharp inflection in capillary condensation/evaporation step specifies that well-ordered MCM-41 nanoparticles were synthesized. TEM image shows the well-ordered hexagonal structure of MSNs. The adsorption capacity of functionalized MSNs was higher than functionalized MCM-41 in which one reason for such behavior might be explained by higher accessibility of pores of functionalized MSNs. This approach was carried out using relatively low-cost and nonhazardous reactants in concentrated reaction medium and also the yield of this approach was high up to 96% by weight.