Preparation Of Oxide Array Nanostructures For Solar Cells

As semiconductor materials, one-dimensional Zn O and Ti O2 array nanostructure have unique physical and chemical properties, they are widely used in solar cells as photo-anode. In this paper, we prepared Zn O nanorod arrays and Ti O2 nanotube arrays, then applied in perovskite-based solar cells and dye-sensitized solar cells, studied the impact of fabricating process on the performance of photovoltaic cells. The main contents of this paper are as follows:1. We prepared Zn O nanorods on FTO(Sn O2: F) glasses by hydrothermal method as photo-anode. Using a two-step method to prepare organic-inorganic hybrid perovskite(CH3NH3Pb I3), and characterized it by different methods. In the process, we studied the influence of hydrothermal time of Zn O nanorods, the concentration of perovskite precursor on the performance of solar cells, resulting that with the nanorods length of about 530 nm, Pb I2 concentration of 1 M, the photoelectric conversion efficiencies of the perovskite-based mesoscopic solar cells were up to 5.8%.2. Since the perovskite-based mesoscopic solar cells was directly prepared through spin-coating Ti O2, Al2O3 and Zn O etc. nanoparticles as mesoporous layer on the dense Ti O2 layer, but the mesoporous layer structure is rather complex, is not convenient for the perovskite to form high quality films, and the hole transport layer to penetrate into the mesopores. In order to solve these problems,We used Zn O nanorods instead of the traditional mesoporous structure, first prepared Ti O2 dense layer on FTO(Sn O2: F) glasses, and hydrothermally grown Zn O nanorods on Ti O2 dense layer to obtain Ti O2-Zn O nanorods heterojunction composite materials. This structure not only improved the quality of perovskite films and was benefit to infiltrate the hole transport layer, but also this heterojunction structure is more conducive to transport electrons, reduce the recombination in the perovskite film, thus greatly improved the short circuit current density of the device, which has reached 24.5 m A/cm2,the highest value that has reported in perovskite-based solar cells.3. Prepared Ti O2 nanotube arrays on titanium foils using a second-anodizition method, investigated the effects of anodizing time on nanotube morphology. Studied the impact of oxidation time and annealing atmosphere of the nanotubes on dye-sensitized solar cells.