Electric field-mediated alignment of electrospun WO₃ nanofibers for enhanced functional properties

Abstract The electrospinning technique enables precise control over the synthesis of nanofibers, including their thickness, size, and uniformity. This study investigates the electrospun synthesis of aligned WO₃ nanofibers, overcoming the challenge of fabricating WO₃ fibers without the need for calcination at high temperature, which has been a limitation in prior research. We explore how and why the distribution of electric fields effects the WO₃ nanofibers’ orientation and functional properties. By adjusting the electric field on the collector plate, we successfully aligned the WO₃ nanofibers and compared their properties with those of randomly oriented fibers produced under identical process conditions. Detailed characterization using techniques such as Raman spectroscopy, UV-Visible spectroscopy, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) revealed significant improvements in the functional properties of the aligned nanofibers. Compositional analysis showed stoichiometric WO₃ formation in the aligned fibers without calcination. Additionally, changes in fiber alignment were found to affect the bandgap, demonstrating how the optical properties of WO₃ nanofibers are affected by fiber orientation. These results demonstrate that controlling nanofiber alignment through electric field distribution can significantly enhance the material's performance, making it promising for advanced applications.