Fabrication of photoelectrode film using anodic oxidation technique for dye-sensitized solar cells

• Highly ordered anatase TiO2 nanotubes prepared by anodic oxidation technique.
• TiO2 nanoparticle-modified single-wall carbon nanotubes (TiO2/SWCNT) by sol–gel method and electrophoretic deposition.
• DSSCs prepared by three layers of photoelectrodes thin films have photoelectric conversion efficiency being as high as 8.52%.

This study uses TiO2 nanomaterials with three different morphologies and carbon nanotubes to fabricate three layers of films for dye-sensitized solar cell (DSSC) photoelectrodes. The three layers of films with different TiO2 morphologies include highly-ordered TiO2 nanotubes, titania nanotubes after calcinations at 550 °C and TiO2 nanoparticle-modified single-wall carbon nanotubes. The study compares the electron transfer performance of the prepared DSSCs are assembled by single-layer, double-layer and triple-layer films of photoanodes. After three different photoanodes are soaked in N719 dye and assembled in DSSCs, their open-loop voltage recession, electrochemical impedance, lifetime, life cycle and effective diffusion coefficient are measured. Electron transfer efficiency of photoanodes and light harvesting efficiency are further analyzed. Results show that the DSSCs prepared by three layers of photoelectrodes films have short-circuit photocurrent density 16.5 mA/cm2, open-circuit voltage 0.835, and photoelectric conversion efficiency being as high as 8.52%. Furthermore, the electron transfer efficiency, lifetime, life cycle and effective diffusion coefficient of DSSCs assembled by triple-layer photoanodes are better than those of single-layer or double-layer photoanodes.