Colloidal liquid aphrons directed growth of sol–gel silica exhibiting bimodal porosities

• Colloidal liquid aphrons was used to prepare bimodally porous silica materials.
• TEOS was utilized as co-constructed template and subsequent silicon source.
• Interfacial confinement hydrolysis–condensation mechanism was proposed.
• Either monolith or hollow sphere is achievable depending on VTEOS/Voil ratio.

We report a new method to prepare bimodally porous, macroporous–mesoporous silica materials utilizing TEOS co-constructed template with colloidal liquid aphrons (CLAs). The macroporous and mesoporous texture of obtained silica is characterized using a combination of fluorescence microscopy, SEM, TEM, and nitrogen volumetric adsorption analysis. The appearance of macropores is attributed to the interfacial confined hydrolysis–condensation of silica source where as the mespore formation is consistent with the pores resulting from the compact packing of nanometer silica particles under weak base-catalysed reaction condition. This bimodally porous silica materials can be prepared either as monoliths or ascisolated spherical particles by adjusting the TEOS concentration in the oil phase.

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