高效稳定的二维钙钛矿太阳能电池：关键材料及器件性能研究

Two-dimentional (2D) perovskite has become a prospective material in the field of solar cells due to its advantages such as unique geometry, tunable optoelectronic properties and excellent environmental stability. However, 2D perovskite still suffer from its low absorption coefficient, low charge mobility and large exciton binding energy, leading to inferior photovoltaic performance. Based on our previous works and the characteristics of 2D perovskite materials, series of organic amine salts containing conjugated aromatic units will be rationally designed and synthesized for application in the 2D perovskite materials. The effect of 2D perovskite structure on the photophysical properties such as light absorption, energy levels, crystallinity and crystal orientation as well as carrier mobility will be studied to find the relationship between the photovoltaic performance and the molecule structure of 2D perovskite materials. Then we will further explore new ways to synthesize high performance 2D perovskite materials and fabricate high efficiency solar cells. At the last stage, the fabrication, characterization and stability measurements of the devices will be studied in details.

二维钙钛矿材料具有独特的几何结构、可调的光电性能和优异的环境稳定性等优点，因而具有诱人的发展前景。然而，现有的二维钙钛矿材料存在吸收系数低、电荷传输能力差和激子耦合能大等问题，导致其光伏性能差，电池效率低下。本项目将在前期工作的基础上，结合二维钙钛矿材料的特点，通过设计合成含共轭芳香基团的有机胺盐，制备二维钙钛矿材料，研究其分子结构对吸收光谱，能级，结晶性和晶体取向，以及载流子迁移率等的影响，同时结合器件测试及形貌分析，揭示二维钙钛矿材料的分子结构与光伏性能之间的本征关系，探索高效二维钙钛矿材料设计合成的新途径，制备高效的二维钙钛矿光伏电池；最后，我们会开展基于二维钙钛矿光伏电池的器件制备、表征、稳定性等方面的系统研究。

具有天然多量子阱结构的二维钙钛矿材料具有可调的光电性能及优异的结构和环境稳定性等优点，因而具有诱人的发展前景。然而，各向异性二维钙钛矿材料存在吸收系数低、电荷传输能力差和激子结合能大等问题，导致相对较差的光伏性能。本项目在前期工作的基础上，结合二维钙钛矿材料的特点，设计合成了系列芳含共轭基团的有机配体，如：噻吩甲脒（ThFA），噻吩双甲铵(ThDAM)，并噻吩双甲铵(TTDMA)，联噻吩双甲铵(BTDMA)，蒽甲铵（AnMA）等。研究了分子结构对吸收光谱，能级，结晶性和晶体取向，以及载流子迁移率等的影响。同时，发展了多种二维钙钛矿薄膜制备技术，结合器件测试及形貌分析，发现了有机半导体层与相邻无机层之间的轨道相互作用，揭示了二维钙钛矿激子分离与传输的内部机制，构筑了高效稳定的二维钙钛矿太阳能电池。目前以通讯作者身份发表致谢本项目的研究论文22篇，包括；J. Am. Chem. Soc. (2篇)，Adv. Mater. (5篇)， Adv. Energy Mater. (1篇)， Nano Lett. (2篇)， ACS Nano (2篇)，ACS Energy Lett. (4篇)等，已授权中国发明专利一项。