In Situ Fabrication of Bi(2)Ti(2)O(7)/TiO(2) Heterostructure Submicron Fibers for Enhanced Photocatalytic Activity

A facile two-step synthesis route combining electrospinning and hydrothermal techniques has been performed to obtain Bi(2)Ti(2)O(7)/TiO(2) heterostructured submicron fibers. Bi(2)Ti(2)O(7) nanosheets were grown on the surface of TiO(2) submicron fibers. The density of the nanosheets increased with higher precursor concentration of the Bi/Ti reaction raw materials. UV-visible (UV-vis) diffuse reflectance spectroscopy indicated that the absorption spectrum of the Bi(2)Ti(2)O(7)/TiO(2) composite extended into the visible-light region. Photocatalytic tests showed that the Bi(2)Ti(2)O(7)/TiO(2) heterostructures possess a much higher degradation rate of rhodamine B than the unmodified TiO(2) submicron fibers under visible light. The enhanced photocatalytic activity can be attributed to the synergistic effect between improved visible-light absorption and the internal electric field created by the heterojunctions. The effective separation of photogenerated carriers driven by the photoinduced potential was demonstrated by the photoelectrochemical analysis. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s11671-016-1408-7) contains supplementary material, which is available to authorized users.