Research On Fabrication And Photoelectric Performance Of Perovskite-Based Solar Cells

Organolead halide perovskite-based solar cells become the new star of solar cells family owing to its long diffusion lengths,ultrafast carrier mobility and large absorption coefficient.In this thesis,the fabrication of the compact TiO₂ layer,mesoporous TiO₂ layer and perovskite layer of perovskite-based solar cells were investigated.On this basis,the FTO glass were used as substrate to fabricate complete perovskite-based solar cells and the influence of different layers made through different method on the photoelectric conversion efficiency of assembled cells was studied.At first,the compact TiO₂ layer was fabricated through Magnetron sputtering.The influence of different thickness of the compact Ti02 layer on the performance of perovskite-based solar cells was studied.Then sol-gel precursor of TiO₂ was spined coating to product the compact TiO₂ layer and morphology of the compact Ti02 layer and performance of the cells which use the compact TiO₂ layers made through differert methods were compared.The result showed that the compact Ti02 layer made through sol-gel method could cover the substrate completely and the cells with it had the best effect and its photoelectric conversion efficiency received 2.83%.About the perovskite layer,at first,one-step was used to fabricate the perovskite layer and the influence of mesoporous TiO₂ layer thickness and spin coating temperature of perovskite on morphology of the perovskite layer and the performance of cells was studied.When the mesoporous TiO₂ layer thickness was 400 nm,and spinning temperature of perovskite was 60 ?,the effect was best,and the photoelectric conversion efficiency received 2.18%.Then the influence of different concentration of PbI₂,spinning temperature of PbI₂ and different perovskite synthesis methods of the two-step method were investigated and discussed.The result showed that using 1moll/L PbI₂ solution at 60? thorogh dip method had the best performance and the photoelectric conversion efficiency received 4.51%.About the mesoporous TiO₂ layer,the effect of different TiO₂ solid content on film character of the mesoporous layer and performance of perovskite-based solar cells were investigated.Result showed that the performance was the best when the solid content was about 5%and its efficiency is 4.78%.Finally,TiCl₄ was used to modify the mesoporous TiO₂ layer.The result showed that it can reduce the dark current and improve the carrier density.The photoelectric conversion efficiency of the cell was increase from 4.78%to 4.96%.