Synthesis of crack-free silica monoliths with cubic mesostructures by a fast evaporation process

By using non-ionic block copolymer amphiphilics as the templates, large-sized, crack-free and transparent silica monoliths with highly ordered cubic (Ia-Sd and Im-3m) mesostructures have been successfully prepared via a fast and simple liquid-paraffin-medium protected solvent evaporation method. The cubic mesostructures of the silica monoliths were studied by small-angle XRD, TEM and nitrogen sorption. Processing temperature is proved to be the key factor to control the evaporation rate and further control the inorganic-organic interaction to preserve the cubic mesostructures. The cubic mesostructured silica monoliths have large surface areas of ∼450 m²/g and pore volumes of ∼0.67 cm³/g, and uniform pore sizes of ∼5.8 nm.