Controllable synthesis of Zn2TiO4@carbon core/shell nanofibers with high photocatalytic performance

Zn2TiO4@carbon core/shell nanofibers (Zn2TiO4@C NFs) with different thickness of carbon layers (from 2 to 8 nm) were fabricated by combining the electrospinning technique and hydrothermal method. The results showed that a uniform carbon layer was formed around the electrospun Zn2TiO4 nanofiber (Zn2TiO4 NFs). By adjusting the hydrothermal fabrication parameters, the thickness of carbon layer varied linearly with the concentration of glucose. Furthermore, the core/shell structure formed between Zn2TiO4 and carbon enhanced the charge separation of pure Zn2TiO4 under ultraviolet excitation, as evidenced by photoluminescence spectra. The photocatalytic studies revealed that the Zn2TiO4@C NFs exhibited enhanced photocatalytic efficiency of photodegradation of Rhodamine B (RB) compared with the pure Zn2TiO4 NFs under ultraviolet excitation, which might be attributed to the high separation efficiency of photogenerated electrons and holes based on the synergistic effect between carbon and Zn2TiO4. Notably, the Zn2TiO4@C NFs could be recycled easily by sedimentation without a decrease of the photocatalytic activity. (C) 2012 Elsevier B.V. All rights reserved.