A solvent-free photochemical route for the preparation of mesoporous inorganic films

An alternative to the Evaporation Induced Self Assembly (EISA) method is described as a fast and simplified approach towards mesoporous silica films. The sol–gel process is photochemically triggered with the aid of photoacid generator (PAG), thereby making mesostructuration independent of film deposition conditions, solvent evaporation and complex chemistry associated with a silica sol. The developed solvent-free synthesis uses non-ionic poly(ethylene oxide)-based surfactants and polydimethoxysiloxane, affording after UV irradiation a film with a wormhole porous framework, and a uniform pore size distribution. The disordered mesostructure was characterized by X-ray diffraction, N2 adsorption, 29Si solid-state NMR and transmission electron microscopy.

We report a simple photochemical methodology towards mesoporous silica thin films by combining photoacid-catalyzed sol–gel process and in situ copolymer templating.Figure optionsDownload as PowerPoint slideHighlights
► Solvent-free methodology towards mesoporous silica film.
► Photoinduced sol-gel process relying on photogenerated superacid catalysts.
► Surfactant self-assembly no longer dependent on the film deposition conditions.
► Spatially-directed UV offers the prospect of photopatterning mesostructured films.