Improved efficiency of dye-sensitized solar cells applied with F-doped TiO2 electrodes

Dye-sensitized solar cells were fabricated using F-doped TiO2 electrodes. The X-ray diffraction patterns of the F doped TiO2 is almost the same as that of pure TiO2, showing that F has little influence on the formation of anatase titania. The influence of dopant F on band energetics and photoelectrochemical properties of nanostructured TiO2 electrodes was investigated. Compared with pure TiO2 electrodes, the Efb of F-doped TiO2 electrodes shifted little in electrolytes containing LiClO4. The total trap densities were remarkably decreased as TiO2 electrodes were doped with F. Finally the F-doped TiO2 electrodes were sensitized with Ru[L2(NCS)2], L = 2,2′-bipyridine-4,4′-dicarboxylic acid and their photoelectrochemical properties were studied. Experiment results showed that the content of F plays an important role in the photoelectrochemical properties. The highest conversion efficiency of 8.07% was obtained with F-doped TiO2 electrodes containing F0.05 (molar ratio) under irradiation of 100 mW cm−2 white light, about 11.3% higher than that of pure TiO2 electrodes.