Influence of Anodization Time on Photovoltaic Performance of DSSCs Based on TiO₂Nanotube Array

Abstract

Highly ordered TiO2 nanotube arrays (TNT arrays) were fabricated by two-step anodization process. In order to further improve the performance of DSSCs, TNT arrays were optimized by changing the anodization conditions to meet the requirements of high-performance photoanode. The photoelectric conversion properties of DSSCs based on P25/TNT arrays double-layer film with different anodization time were investigated and compared. The results show that the conversion efficiency of 4.20% was achieved in double-layer photoanode at 18 h, with an open-circuit voltage (Voc) of 0.65 V and short-circuit current density (Jsc) of 9.98 mA cm−2.

Photocurrent response loss of dye sensitized solar cells owing to top surface nanograss growth and bundling of anodic TiO2 nanotubes

“…Our results could be interpreted by considering either the tube geometry or the progression of recombination of electrons. Although the tube irregularities are introduced due to the formation of nanograss after anodizing for more than 2 h, it must be noted that once the length of TiO 2 nanotube exceeds the photoelectron diffusion length, the electron recombination in the interface of electrode and I − /I −3 redox occurs, so the collection of photogenerated carries becomes low, and consequently, leads to the poor performance of DSSC [ 51 ]. Therefore, electrons encounter more trapping and de-trapping in longer pathways, which causes to decrease the DSSC efficiency [ 27 ].…”