Enhanced photocatalytic performance of WON@porous TiO2 nanofibers towards sunlight-assisted degradation of organic contaminants

Abstract

In the last few decades, TiO₂ has been widely used in different types of photocatalytic applications. However, the relatively large optical band gap (∼3.2 eV), low charge carrier mobility and consequently its low quantum efficiency limit its photocatalytic activity. Herein, we construct a novel nanostructured heterojunction of WON/TiO₂ nanofibers (NFs) by integration of TiO₂ nanofibers synthesized by electrospinning of a polymer solution containing a titanium(IV) butoxide precursor with WON nanoparticles fabricated via annealing of a WO₃ precursor in dry ammonia at 700 °C. The synthesized photocatalysts were characterized using different spectroscopic techniques. Their photocatalytic performance towards the degradation of methyl orange, methylene blue, and phenol as model contaminants was investigated and the charge transfer process was elucidated and compared to that of a TiO₂/WO₃ heterojunction.