Preparation And Characterization Of Perovskite Films

In recent years, haze has become the most popular topic, however, we didn’t put it on the agenda because of the urgent need for economic development."Under the dome" recently sounded the alarm for us again. Because of the renewable of the traditional fossil energy and the destruction to the natural environment from the "three wastes", people train their eyes on the new energy that is cleaner and more productive. Solar energy is a clean, efficient and renewable energy. The main application of the solar energy is the conversion of light into electricity, which also is known as photovoltaic power generation. At present, the most common type on the market is the silicon solar cell, whose highest conversion efficiency can reach about25%. However, either the silicon solar cells or film type photovoltaic device, whose costs are much higher than the traditional energy. By now a new competitor appeared in the world of solar cells——perovskite solar cell, and its efficiency has make a spurt of progress in a few years.The focus of this research was preparation of uniform perovskite films. TiO2and ZnO used as electron transport layer (ETL) and Spiro-OMe-TAD used as hole transport layer(HTL). Influences of the morphology controller on perovskite film formation, especially the uniformity and surface coverage were analyzed.The main research includes the following two aspects:(1) Perovskite solar cell based on mesporous TiO2ETL. The dense TiO2layer prepared by spin coating, the mesoporous TiO2layer formed by screen printing and the organic-inorganic hybrid perovskites film synthesized by sequential deposition. Spiro-OMe-TAD used as HTL and evaporated Ag used as the counter electrode. Finally the following structure FTO/TiO2/CH3NH3PbI3/Spiro-OMe-TAD/Ag and FTO/TiO2/CH3NH3PbIxCl3-x/Spiro-OMe-TAD/Ag were obtained. The composite electrodes are characterized by SEM, XRD, PL and UV-Vis. The structure and optical properties of perovskite films were measured and their impacts on solar cell performance were discussed.(2) Perovskite solar cell based on ZnO nanorods ETL. The dense ZnO seed layer formed by spin coating, the ZnO nanorods obtained by hydrothermal growth and the organic-inorganic hybrid perovskites film synthesized by sequential deposition. Spiro-OMe-TAD used as HTL and evaporated Ag used as the counter electrode. Surface modification of ZnO nanorods with dopamine was studied and the effect of surfactant on the formation of perovskite solar cell was discussed. This part also discusses the factors that affect the uniformity and surface coverage of the perovskite film from several aspects, including spinning speed, concentration, dipping time and annealing temperature.