The Photoelectric Properties Investigation Of The Thin Films Solar Cells With Nanotube Array Photoanode

TiO2nanotube array has been highly concerned for its environment friendly, low cost, large specific surface and chemical stability, therefore, the materials always were used as the photoanode in the dye-sensitized solar cells. However, the photoelectric conversion was inefficient, which was caused by the wide band and the photoelectric capture between the interface of nanotube and titanium substrate. The structure and constitute would influence the conversion efficiency and long-term stability, in this paper, we analyze the photoelectric properties of two kinds of nanotube arrays, and investigate the optimal structures and constitute to enhance the efficiency.(1) The TiO2nanotube array was fabricated by anodic oxidation, and the solar cells were encapsulated by using the nanotube array as the photoanode. By analyzing the photoelectrical properties, the conversion efficiency was correlated with the specific surface, which could be expounded by the large amount of dye adsorption and the optical electronic numbers. On the other hand, the capture of photoelectronic occur in the schottky contact interface would lead to the inefficient photoelectric conversion. Based on the low efficiency of TNT/Ti photoanode, we hypothesis that by optimizing the structure between nanotube array and barrier layer could improve the efficiency. In addition, we also investigate the efficiency of TNT fabricated on the FTO substrate. The results show that, although the lager specific surface would lead to the lager optical electronics number, the thicker barrier layer would block the electronic transaction and increase the compound rate of electronics and holes. The samples’s efficiency would be3.2%with4000nm pipe range.(2) The Fe2O3nanotube array coatings were fabricated on the iron substrate by anodic oxidation, the diameters were40nm-60nm. The parameters of the process would regulate the morphology of nanotube arrays. The nanotube array would disappeared when the oxidation time is20min; the coatings would dissolve when the concentration of fluorinion is9wt%; the caliber was correlated with the voltage.The amorphous Fe2O3would transform to the hematite after annealed at500℃, and posses thermal stability.(3) We carried out the vulcanization experiment using the hematite nanotube array as the precusor. The optimized process was obtained by analyzing and comparing the characteristics of the nanotube array which was fabricated with different process parameters. The FeS2nanotubes were applied in the solar cells, the conversion efficiency reached1.06%, and the results indicated that the FeS2nanotube array possess the potential to replace the TiO2nanotube array for its capacity of photoproduction electronics. In addition, appropriate sulphion would enter into the crystal lattice and produce holes in the crystal, which lead to extend the survive life of electronics, and the pyrite nanotube array would break through the conversion efficiency in the future.