Synthesis of mesostructured silica with tailorable textural porosity and particle size

Mesostructured silica was prepared on three length scales (i.e., nanometric, sub-micrometric and micrometric), with the aid of a non-ionic poly(ethylene oxide) (PEO) surfactant as structure-directing agent under strong acid pH reaction conditions. The size of the primary silica particles can be tuned to between 10 nm and 10 mum by simply adjusting the stirring time during synthesis. The micrometric silica shows a perfectly spherical morphology and a unimodal pore system made up of structural mesopores of similar to6 nm. The other silicas synthesised at the sub-micrometric and nanometric length scales exhibit, in addition to the framework-confined porosity (similar to6 nm), a textural porosity arising from the interparticle voids between the primary particles. (C) 2003 Elsevier B.V. All rights reserved.