Siliceous Unilamellar Vesicles and Foams by Using Block‐Copolymer Cooperative Vesicle Templating

Abstract By employing commercial poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (PEO–PPO–PEO) block copolymers as templates in near‐neutral aqueous solutions in the absence of organic cosolvents, unilamellar siliceous vesicles and nanofoams with ultrahigh pore volumes (> 3 cm³ g^–1) are successfully synthesized. At controlled pH, a tubular micelle → unilamellar vesicle → nanofoam structural transformation is observed by increasing the reaction temperature. It is proposed that the siliceous vesicles are synthesized via a co‐operative block‐copolymer vesicle templating approach, while the siliceous nanofoams are obtained by the fusion of vesicles at increased ionic strength. Compared to literature methods to synthesize siliceous vesicles and foams, our method is convenient, cheap, and produces a high yield. Siliceous nanofoams synthesized by using our approach show superior bioimmobilization capacity over other porous materials for biomolecules with large molecular weight.