Solar Cells Based On CuPc/C₆₀ And Sb₂Se₃/C₆₀ And The Studies By Using Ultrafast Spectroscopy

In modern society,people have more and more demand for energy,and at the same time,the awareness of environmental protection is stronger and stronger.Therefore,more and more clean and sustainable green energy is needed.Solar cells can transform inexhaustible solar energy into electrical energy,which has attracted the attention of governments all over the world.In order to improve the performance of solar cells,we need to deeply understand the microscopic mechanism of the device.In this paper,the generation and recombination process of photo generated carriers in CuPc/C₆₀0 and Sb₂Se₃/C₆₀0 heterojunction have been studied by ultrafast transient spectroscopy.In this paper,we first studied the influence of stacking mode of CuPc on its photophysical properties.We introduce the CuI buffer layer to change the way CuPc stack from"standing"to"lying down".The results show that the CuPc film deposited on a flat surface has higher optical absorption coefficient and longer excited state lifetime.Longer excited state lifetime leads to longer exciton or charge diffusion length and lower recombination probability,so the solar cell based on'flat'CuPc has better performance.Secondly,we have also studied the promising application of Sb₂Se₃ thin film solar cells.Sb₂Se₃ is an ideal absorbing layer material with a gap between1.10eV-1.20eV and a high absorptivity of 105cm-1.Sb₂Se₃ films were prepared by vacuum evaporation process,and their optical absorption,crystal structure and Raman characteristics were characterized.The excited state characteristics were studied by ultrafast transient absorption spectroscopy.A solar cell with a structure of ITO/Sb₂Se₃/C₆₀/AlQ/Al was prepared.