Fabrication and Photovoltaic Properties of Heterostructured TiO₂ Nanowires

One-dimensional heterostructured TiO₂ nanowires were successfully fabricated by an electrospinning technique and modified by hydrolysis. We investigated their structure, morphology, chemical composition, and optical properties by using the X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV-vis spectroscopy. In the case of the photovoltaic performance, the short-circuit current density and cell efficiency of the DSSCs employing single TiO2TiO₂ nanowires and heterostructured TiO₂ nanowires improve from 6.90 to 11.38 mA/cm2 and from 2.56 to 4.29%, respectively. The results show that the photoconversion efficiency of the heterostructured TiO₂ nanowires could be improved by more than ∼67% compared to that of the single TiO₂ nanowires because of the enhanced specific surface area that facilitates dye adsorption.