Synthesis and enhanced photocatalytic activity of Bi/W co-doped TiO₂ nanofibers by one-step microemulsion uniaxial electrospinning

Bi/W co-doped TiO₂ nanofibers with particular morphology were prepared using a uniaxial electrospinning method and microemulsion as a precursor. The nanofibers were characterized by XRD, SEM, EDS, UV–Vis DRS, XPS, N₂ adsorption and desorption analysis, etc. The effect of different Bi/Ti molar ratios on the photocatalytic activity of the composite nanofibers was investigated. The results showed that the incorporation of bismuth and tungsten led to a reduction in the rutile phase fraction within the TiO₂ matrix. Specifically, at a Bi/Ti molar ratio of 0.001, the anatase phase exhibited a grain size of 13.84 nm and a specific surface area of 39.00 m²/g, correlating with the highest photocatalytic efficiency. Under irradiation from a 300 W xenon lamp for 2 h, these nanofibers demonstrated the ability to degrade approximately 98% of methylene blue. The fabrication process for these hollow or multi-channel structured fibers is straightforward, offering a practical approach for the one-step production of composite nanofibers with tailored morphologies for enhanced photocatalytic applications.