Using Rare Earth Modified TiO₂ To Improve The Performance Of Perovskite Solar Cells

With the development of science and technology, use of a large amount of fossil fuel caused serious environmental problems. Therefore, looking for the sustainable new clean energy becomes particularly important. Use of solar energy to realize the high efficiency and low cost of photoelectric conversion is the ideal way to solve the problems. In recent years, based on the organic-inorganic hybrid material of perovskite（CH₃NH₃PbI3） with the advantages of a wide range of light absorption, high light absorption efficiency, low cost, easy preparation has been widely attention. It has a very good research prospect in the field of the solar cells.This paper studied the preparation process of the perovskite solar cells（PSCs） based on TiO₂ via one-step and two-step solution method in the atmosphere. Through the structure characterization and photoelectric performance test, the process conditions of one-step and two-step solution method for PSCs has been obtained successfully. It is found that the PSCs prepared by two-step solution method has better thin film structure, uniform crystal particles, lower PbI2 content and better repeatability. The most important thing is the preparation has robtained the highest efficiency 8.21%, which is higher 2.72% than one-step solution prepared.By comparing solution infiltration method, high temperature diffusion permeation and hydrothermal synthesis method of preparing rare earth doped TiO₂, it is successfully found the most suitable rare earth doping method is hydrothermal synthesis method using La, Ce, Yb and Er as doped rare earth elements. The synthesis of rare earth doped TiO₂ were found doping rare earth elements did not change the crystal structure, but reduced the forbidden bandwidth by characterizing Analysis.By comparing the La, Ce, Yb, Er doped cells performance, it is found Er is the most suitable doping elements for the PSCs. By comparing the PSCs made in different Er-doped molar ratio, it is concluded that 0.5% of the doping molar ratio is the most conducive for PSCs, and the best photoelectric conversion efficiency under the 0.5% molar ratio were 11.74%, which was 3.54% higher than that of the undoped cells.