Electrospun nanofibers of TiO2/CdS heteroarchitectures with enhanced photocatalytic activity by visible light

Herein, we have demonstrated that the electrospun nanofibers of TiO2/CdS heteroarchitectures could be fabricated through combining electrospinning technique with hydrothermal process. The configuration, crystal structure, and element composition of the as-prepared TiO2/CdS heteroarchitectures were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), resonant Raman spectrometer, X-ray photoelectron spectroscopy (XPS). The results indicated that the high-density hexagonal wurtzite CdS crystalline particles of ca. 6-40 nm in diameter were uniformly and closely grown on anatase TiO2 nanofibers. Especially, the light-absorption properties as well as photocatalytic characteristics of pure TiO2 nanofibers and TiO2/CdS heteroarchitectures with different amount loading of CdS were also investigated. The absorption of TiO2/CdS heteroarchitectures was extended to the visible due to effective immobilization of sensitizing agent CdS on TiO2. In contrast with the pure TiO2 nanofibers, the TiO2/CdS heteroarchitectures showed excellent photocatalytic activity by using rhodamine B dye as a model organic substrate under visible-light irradiation. It was worth noting that the cooperative photocatalytic mechanism of the TiO2/CdS heteroarchitectures was also discussed. (c) 2011 Elsevier Inc. All rights reserved.