Abstract:
SiO2 nanoparticles were prepared by sol-gel method with tetraethyl-ortho-silicate(TEOS) as silica source, cetyltrimethylanmmonium bromide(CTAB) as template, and polyethylene glycol(PEG) as disperser agent. The samples were characterized by TEM, SEM, XRD, IR and EDX. The results indicated that the products were rod-like nanoparticles with periodically regular mesopores, and their aspect ratio decreased when lowering the concentration of the silica source, template and disperser agent. If ethanol existed in the reacting system, the shape of the nanoparticles changed from rod to spheroid, further into irregular agglomerate with increase of the volume ratio of ethanol to water. The SiO2 nanorods were silanized and adsorbed Au seeds with average diameter of 3.7 nm on their surface. Then a multi