多孔二氧化钛薄膜涂层的制备和双亲性质研究

Preparation and Amphiphilicity of Macroporous Titania Coating

Wettability is a fundamental property of solids surface, which is governed by both their chemistry and surface morphology. Titania is an interesting semiconductor, whose surface can display supra-amphiphilicity after being irradiated by UV light. This property leads to many attractive potential applications. Howerer, this property gradually loses upon the cessation of the irradiation. It is urgently required to fabricate a titania surface with amphiphilic property, independent on UV light irradiation. Herein, we propose to achieve an amphiphilic titania coating with macropores by dip-coating titania/polymer capsule dispersion followed by the removal of the polymer cores. The porous coating is permanently amphiphilic independent on UV irradiation, which is significantly different from the bulk ones. The amphiphilicity of the porous coating is greatly enhanced up to supra-amphiphilicity by a proper dose of UV irradiation similar to the thin film. Since the size is less than 100 nm, visible light scattering is avoided and the porous coating is transparent. Anatase titania coating with the pores retained is achieved after being calcined at 450 ℃, meanwhile adhesion of the coating on the substrates becomes stronger. The features of the porous coating facilitate its potential applications.