Characteristics of Dye-Sensitized Solar Cells with TiO 2 Stripes.

A TiO 2 strip array with a thickness of 90 nm was fabricated by photolithography and physical vapor deposition. This work utilized the chemical and physical methods to fabricate the TiO 2 strip array. A porous semiconductor layer made of TiO 2 nanoparticles was coated on the TiO 2 strip array. The TiO 2 strip array has a one-dimensional protrusive structure. The energy conversion efficiency (4.38%) of a dye-sensitized solar cell (DSSC) with the TiO 2 strip array exceeded that (3.20%) of a DSSC without a TiO 2 strip array by 37%. In addition, this result was verified by the electrochemical impedance spectra of the two DSSCs. Therefore, the TiO 2 strip array can be used to increase the energy conversion efficiencies of DSSCs. The large energy conversion efficiency of the DSSC with the TiO 2 strip array arises from the large surface area of the one-dimensional protrusive structure and its specific electron transport paths. The DSSC with the TiO 2 strip array has advantages of economical production cost, easy fabrication, and boosting energy conversion efficiency.