Electrospinning WO3 nanofibers with tunable Fe-doping levels towards efficient photoelectrochemical water splitting

In the present work, we reported the fabrication of Fe-doped WO 3 nanofibers via a versatile electrospinning method towards efficient photoelectrochemical (PEC) water splitting. The resultant Fe-WO 3 nanofibers had a high purity in morphology, and the Fe doping levels within the WO 3 nanofibers were controlled in the range from 0.32 to 1.47 at.%, making the band gaps of WO 3 nanofibers tailored from 2.92 to 2.8 eV. The incorporated Fe dopants could not only increase the light absorption, but also improve the charge transport and charge transfer efficiencies, bringing an enhanced PEC activity of the WO 3 nanofiber photoanodes. The WO 3 nanofibers with the optimized 0.32 at.% Fe doping level exhibit the best PEC performance. The mechanism for the enhanced PEC behaviors was proposed.