Flexible Electrospun Carbon Nanofiber/Tin(IV) Sulfide Core/Sheath Membranes for Photocatalytically Treating Chromium(VI)-Containing Wastewater.

We report an efficient method for fabricating flexible membranes of electrospun carbon nanofiber/tin(IV) sulfide (CNF@SnS2) core/sheath fibers. CNF@SnS2 is a new photocatalytic material that can be used to treat wastewater containing high concentrations of hexavalent chromium (Cr(VI)). The hierarchical CNF@SnS2 core/sheath membranes have a three-dimensional macroporous architecture. This provides continuous channels for the rapid diffusion of photoelectrons generated by SnS2 nanoparticles under visible light irradiation. The visible light (λ > 400 nm) driven photocatalytic properties of CNF@SnS2 are evaluated by the reduction of water-soluble Cr(VI). CNF@SnS2 exhibits high visible light-driven photocatalytic activity because of its low band gap of 2.34 eV. Moreover, CNF@SnS2 exhibits good photocatalytic stability and excellent cycling stability. Under visible light irradiation, the optimized CNF@SnS2 membranes exhibit a high rate of degradation of 250 mg/L of aqueous Cr(VI) and can completely degrade the Cr(VI) within 90 min.