Novel F-doped carbon nanotube@(N,F)-co-doped TiO2-δ nanocomposite: Highly active visible-light-driven photocatalysts for water decontamination

Abstract

The development of a facile strategy to prepared titanium oxide with reduced band gap, high electrical conductivity together with good chemical and structural stability that can be widely applied for photocatalysis under visible light holds great appeal. Herein, we reported a novel F-doped carbon nanotube@(N,F)-co-doped TiO2-δ nanocomposite, which was prepared simply by depositing titanium oxide onto electrospun PAN nanofibers containing NH4F via solvothermal synthesis, and the following thermal treatment process. The optimally synthesized nanocomposite shows outstanding photocatalytic performance by removing 77.2% of RhB, 84.1% of MB and 66.2% of Cr(VI) under visible light from a 5 W LED lamp within 60 min, which are approximately 33.6, 6.5 and 6.0 times those over the commercially available pure TiO2 powders, respectively. The greatly improved photocatalytic activity could be attributed to the facts that the co-doping of N and F together with oxygen deficiency enhanced the visible light absorption, and the F-doped carbon nanotube facilitated the exposure of active sites and the separation of photogenerated electrons and holes. This work provides a simple, feasible method for designing and fabricating high-performance titanium oxide photocatalysts.