The Study Of The Fabrication And The Performance Of Highly Efficient And Stable Perovskite Solar Cells Based On ZnO@ZnSe Nanorod Arrays

The development and utilization of renewable and clean solar energy is one of the important ways to solve the energy crisis and environmental pollution problems.Perovskite solar cells have attracted much attention because of their high photoelectric conversion efficiency,simple process and low cost,which have great potential in the future photovoltaic field.In this paper,we fabricated the ZnO@ZnSe core-shell structure nanorod arrays based perovskite solar cell.The effects of ZnSe modification on the performance of perovskite films and devices were investigated.The effects of PVP with different mass concentration on the properties of CS_0.2FA_0.3MA_0.5Pb(I_0.85Br_0.15)₃ mixed perovskite films and devices were also explored.The experimental results show that the photoelectric conversion efficiency of perovskite solar cells modified by ZnSe is up to 11.10%,which is 22%higher than that of perovskite solar cells based on ZnO nanorod array.The improvement of efficiency is mainly due to the suitable energy level structure of ZnO@ZnSe nanorod arrays,which can inhibit charge recombination.Moreover,the modification of ZnSe can improve the optical properties of perovskite films and improve the carrier extraction efficiency between interfaces.In addition,the perovskite films modified by ZnSe and the corresponding devices show better air stability.The improvement of stability can be attributed to the better chemical stability of ZnSe than that of ZnO.The decomposition of perovskite films induced by hydroxyl groups on the surface of ZnO nanorod arrays can be effectively inhibited by coating the ZnSe on ZnO nanorod arrays.On this basis,we also prepared a perovskite solar cells modified with PVP polymer,which achieved a maximum photoelectric conversion efficiency of10.31%,and greatly improved the air stability of the device.The main reason for the improvement of cell efficiency and air stability is that the strong interaction between C=O atom in PVP and Pb²⁺in perovskite can stabilize the crystal structure of perovskite,thus improving the quality of perovskite films,thus greatly improving the optical absorption properties of the films and effectively inhibiting charge recombination.The research work in this paper opens up an effective way to improve the efficiency and air stability of perovskite solar cells.