This article gives an overall view of the mechanisms involved in the mesostructuring that takes place during the formation of surfactant‐templated inorganic materials by evaporation. Since such a method of preparation is well suited to fabricating thin films by dip coating, spin coating, casting, or spraying, it is of paramount interest to draw a general description of the processes occurring during the formation of self‐assembled hybrid organic/inorganic materials, taking into account all critical parameters. The following study is based on very recent works on the meso‐organization of thin silica films using tetraethylorthosilicate (TEOS) as the inorganic source and cetyltrimethylammonium bromide (CTAB) as the structuring agent, but we will show that the method can also be extended to other systems based on non‐silica oxides and block copolymer surfactants. We demonstrate that the organization depends mainly on the chemical composition of the film when it reaches the modulable steady state (MSS), where the inorganic framework is still flexible and the composition is stable after reaching an equilibrium in the diffusion of volatile species. This MSS state is generally attained seconds after the drying line, and the film's composition depends on various parameters: the relative vapor pressures in the environment, the evaporation conditions, and the chemical conditions in the initial solution. Diagrams of textures, in which the stabilized structures are controlled by local minima, are proposed to explain the complex phenomena associated with mesostructuring induced by evaporation.

TiO 2 optical thin films stable to 700 °C, exhibiting 35% volume porosity, more than 100 m 2 ‚g -1 in surface area, fully nanocrystalline anatase framework, and organized mesostructure (cubic Im3m derived), have been stabilized by careful delayed rapid crystallization (DRC) thermal treatments. In-situ time-resolved SAXS and WAXS investigations were simultaneously performed during such treatments. They revealed that a slow and progressive heating to a temperature just below that of the formation of anatase (T c ≈ 400 °C), followed by a long pretreatment at this temperature, stabilizes the amorphous network. A following rapid increase of temperature up to temperatures as high as typically 700 °C, followed by a short residence time at this high temperature, provokes the homogeneous formation of crystalline small nanoparticles and the total elimination of organic residues. The crystallization is accompanied by matter migration through diffusing sintering and pore merging along the [111] directions of the cubic structure, leading to a novel grid-like mesostructure with open porosity. This DRC treatment allows the preparation of highly porous and crystalline anatase films, with thermal stability 200 °C higher than previously reported, that are ideal for energy transfer applications. This emphasizes the role of the treatment method to stabilize transition metal oxide mesoporous materials over extended crystallization at high temperatures. These films exhibit excellent long time stability below 500 °C.