writer：Yanyan Zhao，Yongcai Zhang，Long Yao，Ming Zhang
keywords：Semiconductors, Nanocomposites, Functional, Powder technology
source：期刊
specific source：Materials Letters
Issue time：2014年

This paper reports the novel synthesis and evaluation of visible-light-active SnS₂/SnO₂nanocomposite for photocatalytic reduction of aqueous Cr(VI). An alternative one-step chemical synthesis method, which was based on heating the mixture of Sn, S and NH₄Cl powders in air at 320 °C for 3 h, was proposed for the synthesis of SnS₂/SnO₂nanocomposite. The structure, composition and optical property of the as-synthesized SnS₂/SnO₂ nanocomposite were characterized by X-ray diffraction, wavelength dispersive X-ray fluorescence spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy and UV–vis diffuse reflectance spectrum. The photocatalytic activity of the as-synthesized SnS₂/SnO₂ nanocomposite was tested in the reduction of aqueous Cr(VI) under visible-light (λ>420 nm) irradiation, and compared with that of SnS₂ nanoflakes. It was observed that the as-synthesized SnS₂/SnO₂nanocomposite exhibited much higher photocatalytic activity than SnS₂ nanoflakes in the reduction of aqueous Cr(VI) under visible-light (λ>420 nm) irradiation, suggesting SnS₂/SnO₂ nanocomposite is a more promising visible-light-active photocatalyst as compared with SnS₂. Besides, the electrochemical impedance spectroscopy analysis supported the photocatalytic results.