Effects of preparation conditions on the morphology and photoelectrochemical performances of electrospun WO3 nanofibers

The effects of calcination temperature, precursor content, holding time and heating rate on the morphology of WO3 nanofibers (NFs) prepared by electrospinning technology have been investigated systematically. The X-ray diffraction (XRD) patterns using Rietveld method indicated that average crystalline sizes of nanoparticles of WO3 NFs increase with increasing calcination temperature. Also, the crystallinity of the nanofibers increases with the rise of calcination temperature. The suitable precursor contents and holding time facilitate the formation of continuous and uniform NFs. The samples prepared by different heating rates showed that the WO3 NFs fabricated with heating rate of 5 °C/min possess the smallest and uniform nanoparticle sizes. The X-ray diffraction (XRD) patterns using Rietveld method exhibited that different heating rate had no significant influence on the crystallinity of WO3 NFs. Additionally, the experimental results of photocurrent responses and electrochemical impedance indicate that the WO3 NFs prepared by different heating rate have different photoelectrochemical performances.