含有机生色团的有机/无机杂化二维钙钛矿的电致发光性能研究

Organic-inorganic hybrid perovskites with emitting properties show merits of tunable bandgap, solution processible and inexpensive, starting to be the study focus in optoelectronic materials. Among them, the two-dimensional (2D) perovskites consisting of organic amines and halides show the binding energy of hundreds of millivolts with the property of luminescence, making them suitable emitter in light emitting diodes. Currently, the study of light emitting diodes based on 2D perovskites is limited. In order to enhance the luminance properties, this project aims to synthesize 2D perovskites with halides and organic diammonium molecules containing a chromophore. We propose to investigate the influence of degree of crystallization, film forming process and annealing condition et al. of perovskite on the performance of light emitting diodes. Throughout this project, we aim to understand the internal connection of the crystal structure, opital and electrical properties of 2D perovskites with the performance of devices, and to clarify the emission mechnism. We believe our work will not only provide new sight in designing high efficient 2D perovskite but also provide new ideas into optimizing device performance.

有机/无机杂化钙钛矿发光材料具有带隙可调、可通过溶液加工、价格低廉等优点，开始成为光电材料的研究热点。其中由有机胺和无机卤化物交替堆叠的二维钙钛矿，激子束缚能达几百毫伏，具有良好的发光特性，可作发光二极管中的发光材料。目前对基于二维钙钛矿的电致发光二极管的研究有限。本项目目标旨在设计含发光基团的有机双胺类材料，与无机卤化物合成二维钙钛矿以提高发光特性。围绕目标考察钙钛矿材料结晶程度、成膜工艺、退火条件等对发光器件性能的影响。通过项目实施，将从二维钙钛矿材料的晶体结构、光学和电学性质多方面掌握材料属性和发光器件性能参数之间的关系，进而深入澄清发光来源。为新型高效二维钙钛矿材料的开发提供理论指导，为器件性能的优化提供新的思路。

有机/无机杂化钙钛矿发光材料具有带隙可调、可通过溶液加工、价格低廉等优点，开始成为光电材料的研究热点。其中由有机胺和无机卤化物交替堆叠的二维钙钛矿，激子束缚能达几百毫伏，具有良好的发光特性，可作发光二极管中的发光材料。鉴于其在电致发光二极管中仍缺乏研究，本项目旨在设计含发光基团的有机双胺类材料，与无机卤化物合成二维钙钛矿以提高发光特性并应用于电致发光二极管。以苯胺类化合物为二维单元合成一系列不同烷基链长度的二维钙钛矿，发现烷基链较长时更容易形成钙钛矿。 在此基础上，我们合成了含有发光基团的二胺盐，制成相应的钙钛矿器件，启亮电压为5V， 最大外量子效率为0.03%。通过对比光谱发现，钙钛矿的发光来源是有机发光基团。由于这类大体积双胺较难形成高质量二维钙钛矿，我们有开发了含较小体积发光基团的单胺盐，以减少结晶过程的阻碍，最终得到结晶性较好的二维薄膜。