Enhanced efficiency for dye-sensitized solar cells with ZrO2 as a barrier layer on TiO2 nanofibers

Abstract Due to its low cost and high efficiency, dye-sensitized solar cells have been widely studied. As all of known, nanoparticles are not conducive to the separation and transmission of electrons and holes. One-dimensional (1D) TiO 2 nanofibers (NF), synthesized via electrospinning method, were used to replace the nanoparticles film. It offered a direct pathway and can absorb dyes to improve the efficiency, which had revealed distinct properties as a photoanode in DSSC. In addition, ZrO 2 , as a barrier layer on NF, enhanced the efficiency of dye sensitized solar cell. Moreover, the ZrO 2 layer can availably enhance the efficiency by preventing recombination of electron-hole between TiO 2 and the dye/electrolyte. Electrochemical Impedance Spectroscopy (EIS) measurements provided evidence that the coating ZrO 2 reduced recombination losses at the photoanode-TiO 2 -dye|I 3 − /I − electrolyte interface, which passivated localized surface states. Results of photovoltaic measurements of the NP/NF/ZrO 2 DSSC revealed that a barrier layer of ZrO 2 could improve efficiency. The NP/NF/ZrO 2 -based devices exhibited a higher efficiency of 6.72% than that of NP/NF (6.14%). This work provides a novel approach for the rational design of the photoanodes in DSSC, which also implies the potential application of this structure in other type of solar cells.