The Synthesis And Photoelectric Study Of Organolead Halide Perovskites

Organolead halide perovskites, the organic-inorganic hybrid compounds, areorderly self-assembled with organic and inorganic molecules. They are generally easyprocessing, low cost, with high electron mobility, photovoltaic and thermal stability,which make these materials are extremely promising for the application of low-costsolar cells.In this thesis, we mainly employed lead iodide as the inorganic component toreact with different organic units to form various organic-inorganic perovskitematerials. Thereby to replace traditional organic dyes to fabricate organic leadhalide-based solar cell devices. Based on the XRD, SEM, UV-Vis characterization ofperovskite materials and the photoelectric conversion efficiency measurements of solarcell devices, the effect of the organic units on the crystal structure, visible absorptionspectra of the synthesized perovskite materials were systematically explored. Theinfluence of the dense layer, mesoporous layer, perovskite layer, hole transport layerand the metal electrodes on the device efficiency were also deeply investigated. Finally,the optimized parameters for constructing high efficiency perovskite solar cells wereobtained.Wherein the formamidine (NH2CH=NH) was used to substitute methylamine(CH3NH2) to synthesize the new perovskite material NH2CH=NH2PbI3(FAPbI3) with aband gap of1.43eV and valence band of-5.4eV. The solar cells based on the FAPbI3and the Cl doped FAPbI3(FAPbI(3-x)Clx) were fabricated and studied. An efficiency of7.51%was achieved up to now. It is worth noting that the new FAPbI3perovskite wasmore promising than the traditional MAPbI3for the photovoltaic devices in terms of itsproper band gap value and high thermal stability.