Low-temperature synthesis of regenerable TiO2−xNx nanocrystals in Nafion membrane and the promotive effect of Nafion in photocatalysis and N-doping

Monodisperse TiO2−xNxnanocrystals were successfully synthesized in Nafion membrane at low temperature in a convenient way. Several characterization techniques, X-ray diffraction (XRD), UV-vis absorption spectra and X-Ray Photoelectron Spectroscopy (XPS) are combined in order to determine the crystal phase, grain size, optical absorption, and state of the resultant oxynitride chemical bonding. The photocatalytic activity and stability of the homogeneously dispersed TiO2−xNxnanocrystals embedded in Nafion membrane were evaluated through a study of the decomposition of Methylene Blue under visible light irradiation. It was found that the photocatalytic activity of the TiO2−xNxnanocrystals can be enhanced efficiently by re-nitridation. Also, the form of Nafion, acidic or salt, affected photocatalytic activity.