三元阳离子和二元阴离子共存调控(FA1-x-yMAxCsy)PbI3-zBrz单晶稳定性和光电性能的贡献机制研究

有机-无机杂化钙钛矿耐热、湿、光不稳定性严重制约了其在太阳能电池和光探测器等光电器件的产业化应用。在保持优异光电转换效率的同时，三元阳离子和二元阴离子共存的(FA1-x-yMAxCsy)PbI3-zBrz钙钛矿材料的稳定性呈现大幅度提升。然而，各组分对稳定性提升的内在原因及对光电性能的贡献机制尚不明确。本项目拟通过调控多组分前驱体溶液稳定性的前提下，生长不同组分含量的(FA1-x-yMAxCsy)PbI3-zBrz单晶；利用单晶排除薄膜中晶界的干扰及准确提供晶体结构信息的优势，揭示多元组分对晶体结构和光学性质的影响规律；探讨晶体结构和单晶耐热、湿、光稳定性的构-效关系；借助于瞬态荧光显微和光电探测器，揭示组分对载流子传输与复合特性的贡献机制，及对探测器光电性能的影响规律；并构筑高性能、高稳定性的光探测器。项目的研究将为设计新型、高稳定性的多元混合离子钙钛矿材料提供理论指导和技术支持。

The instabilities of organic- inorganic hybrid perovskite against heat, moisture and light are the major hurdle for their photoelectronic industry applications, like solar cells and photo-detectors. The coexistence of triple cations and binary anions in (FA1-x-yMAxCsy)PbI3-zBrz perovskites can greatly enhance their intrinsic stabilities without sacrificing the conversion efficiency. However, the underlying mechanisms of the triple cations and binary anions to the stabilities and photo electronic properties remains unclear so far. Grounded on the premises of regulating the precursor stability, a series of (FA1-x-yMAxCsy)PbI3-zBrz single crystals will be grown in this project. Owing to the free of grain boundaries and the accuracy on gaining crystal structure information by the use of single crystals, the contributions of each components to both crystal structure and optical properties will be unambiguously revealed. Meanwhile, the correlation between the crystal structure and the stabilities against heat, moisture and light will be clarified. By virtue of transient fluorescence microscopy and photo-detectors, the component-dependent characteristics of charge carrier transport and photo electronic performances of the photo-detector will be systematically investigated, which would finally guide the construction of high performance and high stability photo-detectors. The investigation of this project will provide theoretical guidance and technical support for designing novel multi-components mixed perovskite materials with high stabilities.