Study On Application Of CuSCN And CuI As Hole Transport Layers In Perovskite Solar Cells

Organic metal halide perovskite solar cells are widely concerned because of their high conversion efficiency,and become one of the most promising materials in photovoltaic field.In this thesis,CuI and CuSCN are used as hole transport layers and the modification layer of polymer hole transport layer to improve the performace of p-i-n perovskite solar cells.Attributing to the introduction of CuI modification layer,the interface defects between PTAA hole transport layer and perovskite active layer are reduced,the morphology of perovskite active layers was improved,and the high performance perovskite solar cells were prepared.The main contents of this thesis are as follows:(1)CuI and CuSCN are used as hole transport layer to substitute for polymer hole transport layer.The results show that their morphology depends heavily on post treatment.By suitable post treatment of CuI and CuSCN,compact and hole-free inorganic hole transport layers are prepared.The conversion efficienciy of the perovskite solar cells with CuI and CuSCN as hole transport layers respectively achieves 15.92% and 14.17%.(2)CuI is used to modify the surface of polymer hole transport layer material poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA)for the sake of improving the crystallization quality of perovskite active layers.The results that the crystallization of perovskite is improved,and a thin film with larger and uniform crystal grains and good compactness is formed.At the same time,the interface contact between the perovskite layer and the hole transport layer becomes better.The PL and TRPL spectra as well as the ideality factor show that the defects of the perovskite film on CuI modified PTAA layer are reduced.The efficiency of the perovskite cell is increased from 16.79% to 20.81% by the modification of CuI to the surface of PTAA.