Synthesis of porous and trigonal TiO2 nanoflake, its high activity for sonocatalytic degradation of rhodamine B and kinetic analysis

Porous and trigonal TiO2 nanoflakes (p-TiO2) have been synthesized via a simple hydrothermal calcination process, and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-vis absorption/reflection spectroscopy (UV-vis). The X-ray diffraction patterns of the as-prepared samples show that p-TiO2 has an anatase structure. Transmission electron microscopy images indicate that p-TiO2 consists of sheet-like particles with numerous pores about 100 nm in diameter. Ultraviolet-visible reflection spectroscopy exhibits that the absorption edge acquires a blue shift with increased calcination temperature. The effects of the calcination temperature, catalyst dosage, and initial rhodamine B (RhB) concentration on the sonocatalytic activity for removing RhB are investigated in detail. The results show that the as-prepared p-TiO2 obtained at the optimal calcination temperature of 600 degrees C exhibits a higher sonocatalytic activity than commercial P25. Based on the effects of the initial RhB concentration on sonocatalytic activity, the sonocatalytic degradation kinetics of RhB is also investigated. (C) 2012 Elsevier B.V. All rights reserved.