Bi4Ti3O12 nanosheets/TiO2 submicron fibers heterostructures: in situ fabrication and high visible light photocatalytic activity

Abstract
In this paper, a facile two-step synthesis route combining an electrospinning method and hydrothermal technique has been accepted as a straightforward protocol for the exploitation of Bi4Ti3O12 /TiO2 heterostructures which are composed of Bi4Ti3O12 nanosheets on the surface of TiO2 submicron fibers. The thickness of the as-grown nanosheets was about 20 nm and the size of the nanosheets increase with the increase of precursor concentration. Photocatalytic tests display that the Bi4Ti3O12 /TiO2 heterostructures possess a much higher degradation rate of rhodamine B (RB) than the unmodified TiO2 submicron fibers under visible light. The enhanced photocatalytic activity can be attributed to the extended absorption in the visible light region resulting from the Bi4Ti3O12 nanosheets, and the effective separation of photogenerated carriers driven by the photoinduced potential difference generated at the Bi4Ti3O12 /TiO2 junction interface.