杂化金属卤化物钙钛矿晶体的合成制备

发布时间：2018-01-13 14:25

本文关键词：杂化金属卤化物钙钛矿晶体的合成制备　出处：《南京大学》2017年硕士论文　论文类型：学位论文

【摘要】：杂化金属卤化物钙钛矿晶体材料是由有机组分和无机组分通过有序自组装的形成,合成的有机无机杂合物,具有易合成,生产成本低廉的特点,可以使用卷对卷技术(Roll-to-Roll)进行大规模的工业化生产,有利于以后市场的推广。在分子尺度上,杂化金属卤化物钙钛矿晶体材料是有机无机杂合物,拥有有机物和无机物的部分性质,并且杂化金属卤化物钙钛矿晶体材料属于有直接带隙的新型半导体类的材料。因此在发光器件或者是探测器件中,杂化钙钛矿晶体材料可以被用来作为器件的发光层或者是有源层。杂化金属卤化物钙钛矿结构的载流子迁移率较高,拥有可调节的禁带宽度,扩散长度可以达到微米量级。在太阳能电池、发光二极管、光探测器和激光等应用领域,杂化金属卤化物钙钛矿拥有很大的竞争力。由于杂化金属卤化物钙钛矿晶体在光电子领域有着很大的潜在应用价值,因此我们比较了目前杂化金属卤化物钙钛矿晶体材料的多种合成方法,并在这些方法的基础上:1、提出了 MAI醇溶液密封法,首先在FTO衬底上旋涂一层PbBr2薄膜,再将衬底放入到MAI醇溶液中,不但可以利用醇溶液隔绝外界的氧气(02)和水气(H20),避免钙钛矿在形成过程中分解,也可以使PbBr2和MAI更加充分的反应,从而得到高质量的有机无机杂化金属卤化钙钛矿晶体。MAI醇溶液密封法的优势就在于在无手套箱的条件下,能够以低成本、更加简便、可重复的方式获得稳定和高质量的杂化钙钛矿晶体薄膜。2、通过XRD、EDS以及PL谱的测试,我们对获得的杂化金属卤化物钙钛矿晶体材料进行了表征,研究影响杂化钙钛矿晶体材料的因素,进一步地分析杂化钙钛矿晶体材料的形貌演化方面的机制。通过对合成的钙钛矿试验参数的调节,包括DMF的浓度和浸泡时间因素,实现了对钙钛矿形貌的控制,观察到其形貌从纳米立方到纳米线,再到纳米片,最后成为微米级立方晶体的演化过程。在生长初期,钙钛矿纳米晶体受到DMF溶液控制,趋向于一维生长,但随着钙钛矿量的增加,由于能量最低原则,驱使钙钛矿晶体三维生长成微米级立方晶体。实验观察到制备的钙钛矿晶体具有很强的光致发光现象,发光峰位可以从746nm到770nm变化,这种红移是由于I-离子不同程度的取代晶格中的Br-离子。
[Abstract]:Hybrid metal halide perovskite crystal materials are composed of organic and inorganic components through orderly self-assembly, the synthesis of organic-inorganic hybrids has the characteristics of easy synthesis and low production cost. Roll-to-Roll technology can be used for large-scale industrial production, which is conducive to the future promotion of the market, in the molecular scale. Hybrid metal halide perovskite crystal materials are organic-inorganic hybrids with some properties of organic and inorganic compounds. And the hybrid metal halide perovskite crystal material belongs to a new type semiconductor material with direct band gap. Hybrid perovskite crystal can be used as the luminescent layer or active layer of the device. The hybrid metal halide perovskite has high carrier mobility and adjustable bandgap. Diffusion lengths can reach microns. In solar cells, light-emitting diodes, photodetectors and laser applications. Hybrid metal halide perovskite has great competitive power. Because hybrid metal halide perovskite crystal has great potential application value in optoelectronics field. Therefore, we compare various synthesis methods of hybrid metal halide perovskite crystal materials, and on the basis of these methods, we propose MAI alcohol solution sealing method. Firstly, a PbBr2 film is spin-coated on the FTO substrate, and then the substrate is put into the MAI alcohol solution, which can not only use the alcohol solution to insulate the oxygen (02) and the water vapor (H20). To avoid the decomposition of perovskite in the formation process, PbBr2 and MAI can be more fully reacted. Thus, the advantage of high quality organic and inorganic hybrid metal halide perovskite crystal. Mai alcohol solution sealing method is that it can be cheaper and simpler under the condition of no glove box. Stable and high quality hybrid perovskite crystal thin films. 2 were obtained in a repeatable manner and tested by XRDX EDS and PL spectra. The hybrid metal halide perovskite crystal materials were characterized and the factors affecting the hybrid perovskite crystal materials were studied. The mechanism of morphology evolution of hybrid perovskite crystal materials was further analyzed. The parameters of the synthetic perovskite were adjusted including the concentration of DMF and the soaking time. The morphology of perovskite was controlled. The morphology of perovskite was observed from nanocrystalline to nanowire, then to nanoscale, and finally to the evolution of micron cubic crystal. Perovskite nanocrystals are controlled by DMF solution and tend to grow in one dimension, but with the increase of perovskite content, the energy is the lowest. It is observed that the prepared perovskite crystal has strong photoluminescence, and the luminescence peak can change from 746 nm to 770 nm. This redshift is due to the varying degree of substitution of I-ions for Br- ions in lattice.
【学位授予单位】：南京大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O78

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