Self-Assembly of Large-Scale Floating TiO₂ Nanorod Arrays at the Gas–Liquid Interface

This paper describes a facile one-step synthesis of large-scale floating TiO2 nanorod arrays via a hydrothermal reaction without using any surfactants, which opens a new way to prepare floating photocatalysts for photodecomposition of floating organics and free-standing nanorod arrays for flexible dye-sensitized solar cells. A general model is developed to analyze the driving force for the floating TiO2 film, which may be also useful for other two-dimensional materials to determine the obtainable size of an arbitrary shaped film floated by surface tension and buoyancy.