Title screen

[Ref.: p. 16 (35 tit.)]

Mesoporous silica composed by small nanoparticles has been synthesized by a modified neutral S0I0 templating route method (S0, neutral primary amine surfactant; I0, neutral inorganic precursor). Decreasing the polarity of the medium and tuning the composition of the S0I0 pair allow the formation of silica nanoparticles that are agglomerated into silica fractal or sponge-like structures. Those nanoparticles conform the building blocks of the neutral S0I0 method. In this work for the first time they are observed isolated by HRTEM. On the other hand, the addition of metal oxides triggers the formation of aggregates containing unusually small silica nanoparticles, i.e. smaller building blocks that in bare silica, in the range of 2–4 nm. Further, through the impregnation of a gold precursor post-synthesis, ultra small gold nanoparticles (1 nm) were embedded in the final silica nanostructures upon calcination of the organic precursors. FTIR and UV–vis spectroscopies, TEM and SEM, XRD and N2 absorption were used to characterize the resultant materials.