TiO₂/CH₃NH₃PbI₃/CuI Perovskite Thin Film Solar Cell

As the energy crisis and environmental problems have become increasingly acute,people are trying to find cheaper and cleaner energy to solve this problem.Solar energy has attracted people's attention.One of the most effective ways to use solar energy is solar cells.Since the introduction of perovskite solar cells in 2009,the conversion efficiency of solar energy has increased rapidly from 3.8%to 23.7%in 10 years,which has basically reached the development of silicon and compound solar cells for decades.It is not only due to the unique properties of perovskite?such as appropriate band gap,high extinction coefficient,long carrier diffusion length and carrier lifetime?,but also related to the band matching of perovskite materials with electron transport layer and hole transport layer,and the electron hole transport rate.?1?By controlling the solution of the precursor of titanium dioxide,nanorods,nanotubes and nanosheets are prepared,which can realize the precise preparation of various nanomaterials,provide a good interface contact between the electron transport layer and the perovskite layer,and then the conversion efficiency of perovskite solar cells can be improved.?2?High quality perovskite thin films were prepared by a novel solution evaporation-immersion method.Firstly,porous PbI₂ is prepared by adjusting the concentration of precursor PbI₂.Due to the existence of holes in PbI₂,MAI can diffuse completely into the whole PbI₂ film and realize the complete transformation of PbI₂.Moreover,the holes provide enough growth space for CH₃NH₃PbI₃,thus increasing the grain size of perovskite and improving the quality of perovskite films.The highest efficiency of solar cells prepared by using cuprous iodide?CuI?as the hole transport layer is 6.14%,while the efficiency of traditional evaporation immersion method is 4.69%.Compared with traditional evaporation immersion method,the performance of solar cells is improved by nearly30%.