Well-dispersed Pt nanocrystals on the heterostructured TiO2/SnO2 nanofibers and the enhanced photocatalytic properties

Heterostructured TiO2/SnO2 nanofibers deposited with ultrafine Pt nanocrystals (Pt-TiO2/SnO2) were prepared by combining electrospinning and polyol reduced method. The samples have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Xray photoelectron spectroscopy (XPS), UV-vis diffuse reflection spectroscopy (DRS), photoluminescence spectra (PL) and nitrogen adsorption-desorption isotherm analysis. The results indicated that heterojunctions formed between TiO2 fibers and SnO2 fibers in the side-by-side structure with Pt nanocrystals in a crystallite size of 4.5 nm uniformly deposited on them. The Pt-TiO2/SnO2 nanofibers photocatalysts possessed large surface-exposure area, broadened spectral response range, stable recyclability, and efficient charge separation properties. Furthermore, the photocatalytic activity of Pt-TiO2/SnO2 for the degradation of methylene blue was much higher than that of bare TiO2 and SnO2 nanofibers, which could be ascribed to the formation of heterojunctions in the TiO2/SnO2 nanofibers and the rapid transportation of electrons to the surface assisted by Pt nanocrystals. The results presented herein provide new insights into heterostructured materials as high-performance photocatalysts and their potential use in environmental protection. (C) 2014 Elsevier B. V. All rights reserved.