Mesoporous silicate−surfactant composites were prepared via washing of as-synthesized silicate−surfactant−expander materials in appropriate solvents. The expander can be generated in situ from the surfactant
decomposition under high-temperature conditions, or supplied externally at the stage of the synthesis or
postsynthesis hydrothermal treatment. The washing removed the expander as well as a minor part of the
surfactant ions present and thus opened the mesopores whose walls were covered by a relatively dense layer
of surfactant ions. Depending on the synthesis method for silicate−surfactant−expander composites, both
ordered and disordered mesoporous silicate−surfactant composites were obtained with narrow pore size
distributions and a wide range of adjustable pore sizes (4−12 nm). Despite the fact that these materials contained
25−35 wt % of surfactant, they exhibited large BET specific surface areas (360−550 m2 g-1) and total pore
volumes (from 0.4 to as large as 1.8 cm3 g-1). It is postulated that the surfactant retained in the silicate−surfactant composites is bonded to the silicate walls via electrostatic interactions, which are originally
responsible for the formation of silicate−surfactant or silicate−surfactant−expander mesophases. The
mesoporosity of the composites is mostly constituted by the space initially occupied by expander, which was
later removed upon washing. The synthesis approach described herein is the first successful method for synthesis
of ordered and disordered mesoporous silicate−surfactant composites with hydrophobic surfaces, the latter
being predominantly formed by long alkyl chains of surfactant ions.