One-step preparation of silver nanoparticles confined in functionalized-free SBA-15 channels

摘要

Supported Ag nanoparticles were successfully prepared by a one-step in situ procedure within channels of SBA-15 mesoporous silica. The reaction was carried out in N,N-dimethylformamide (DMF) at 25 ° C with no need for silica surface functionalization or demanding time-consuming steps, and presents important advantages over the usual method. The small-angle X-ray scattering (SAXS) pattern of SBA-15 presents well-defined reflections associated with P6mm hexagonal symmetry. TEM micrographs of supported Ag nanoparticles (SBA-15/Ag) clearly show the presence of spheroidal and elongated Ag nanoparticles that are confirmed by surface plasmon resonance band in the UV-vis absorption spectrum. No evidence of Ag nanoparticle agglomeration was observed throughout the inorganic matrix. Ag nanoparticle formation within channels of SBA-15 decreases its specific surface area and total pore volume, as evidenced by nitrogen adsorption-desorption isotherms, with no damage to the silica framework. The method shows itself to be very efficient, fast and convenient for the synthesis of supported Ag nanoparticles in SBA-15 channels.