Coaxial electrospun TiO2/ZnO core–sheath nanofibers film: Novel structure for photoanode of dye-sensitized solar cells

Novel TiO2/ZnO core–sheath nanofibers (NFs) film was fabricated through an extraordinary coaxial electrospinning technique. Dye-sensitized solar cells (DSSCs) were assembled using the TiO2/ZnO NFs film as photoanode. FESEM, TEM, FTIR, XRD, XPS and UV–vis were used to characterize the NFs electrode film. Photocurrent–voltage (I–V) characteristic, incident photo-to-current conversion efficiency (IPCE) spectrum, and electrochemical impedance spectroscopy (EIS) measurements were performed to evaluate the DSSCs performance. The results reveal that the DSSCs based on the TiO2/ZnO core–sheath NFs are superior to their bare TiO2 NFs-based counterparts. Compared with the latter, the overall energy conversion efficiency was enhanced from 4.47 to 5.17%. And the possible mechanism for this enhancement was discussed.