Ionic-liquid-assisted growth of flower-like TiO₂ film on Ti substrate with high photocatalytic activity

Flower-like anatase TiO₂ films on Ti substrate were prepared via direct oxidation in H₂O₂ solution assisted with [Bmim]BF₄ ionic liquid. The promotion effect of ionic liquid to both the growth of anatase TiO₂ crystal and the formation of flower-like morphology was demonstrated. The formation process of flower-like TiO ₂ film was investigated via adjusting the oxidation reaction time. During the photo-degradation of aqueous rhodamine B solution under UV light (λ = 365 nm) in rotating disk reactor, the obtained flower-like TiO ₂ film exhibited efficient decomposition of rhodamine B, which could be contributed that the flower-like morphology of TiO₂ film with high anatase crystallization and mesoporous structure led to the enhancement of light harvesting and reactant adsorption. Furthermore, the excellent stability of TiO₂ film during the photo-degradation reaction was resulted from the stable combination of TiO₂ film with Ti substrate.