High conversion efficiency of pristine TiO2 nanotube arrays based dye-sensitized solar cells

We prepared highly-ordered titanium dioxide nanotube arrays （TNAs） by anodizing Ti foils in F-containing electrolytes. The crystalline nature and morphology of the TNAs were studied using X-ray diffraction patterns and scanning electron microscopy. We found the morphology of TNAs affects the light-to-electricity conversion efficiency （17） of dye-sensitized solar cells （DSSCs）. The efficiency of DSSCs reached 5.95% under the condition of light illuminated from the counter electrode. The high efficiency of TNA-based DSSCs was attributed to the neat top surface of TNAs, which allows more dye molecule loading on the surface of the TiO2 nanotubes, and fewer electron recombination centers and a low interface resistance of integrated TNAs.