Photocatalytic degradation of methylene blue by TiO2/Nd2O3 composite thin films

Abstract

To improve the photocatalytic property of TiO2 thin films, the composite thin films of TiO2/Nd2O3 structure were fabricated by electron-beam physical vapor deposition method, and the photocatalytic property of the fabricated films was experimentally studied in the present work. The XRD and Raman analyses show that the TiO2/Nd2O3 films are mainly hexagonal crystalline phase of Nd2O3. The XPS analysis for the chemical state changes of Ti, O and Nd of the basic elements in the films is confirming the electron flow in the internal electric field which generated in the TiO2/Nd2O3 films. The surface morphology shows the lattice distortion which affects the changes in the energy band structure. Moreover, the formation of n-n homojunctions improved the separation efficiency of electrons and holes, and enhanced the catalytic activity. The photocatalytic performance for the methylene blue target dye shows that the sample with TiO2 thickness of 20–25 nm has better performance, high degradation efficiency and high reaction rate.