二茂铁基星状空穴传输材料的合成及在钙钛矿电池中的性能研究

Efficient hole transporting materials plays an important role in the improvement of the performance of perovskite solar cell (PSC). This project aims to design and synthesis of star-shaped molecules containing a triphenylamine core, ferrocenyl end groups and thiophene-based conjugated bridges, and they are used as a hole-transporting materials to realize high hole mobility in PSC. The ferrocenyl end groups have very strong electron donating ability, which promotes electron transfer to the triphenylamine core so as to enhance the hole mobility of the star-shaped materials. The triphenylamine-based star-shaped structure and long-chain alkyl groups can reduce the molecular aggregation, improve the film forming properties of the hole-transporting materials, achieve good contact performance with the perovskite layer, reduce series resistance, and reduce carrier recombination. By changing the structure of thiophene-based conjugated unit, the molecular energy levels of the hole-transporting materials can be adjusted to match with the energy levels of perovskite and counter electrode. In this project, the design, synthesis and the effect on the hole mobility of the ferrocenyl-based star shaped hole-transporting materials are the main thread, in order to study the influence of ferrocenyl groups and thiophene-based conjugated unit on the properties of the star-shaped hole-transporting materials and to explore the relationship of the hole-transporting materials with their hole mobility and their interaction mechanism in PSC. The research achievements provide new ideas and experimental basis on the development of novel hole-transporting materials and the fabrication of high-efficiency perovskite solar cells.

高效空穴传输材料对提高钙钛矿太阳能电池（PSC）的性能具有重要作用。本项目拟设计合成以三苯胺为核、二茂铁为端位基团、噻吩环为共轭桥的星状分子，作为空穴传输材料，在PSC中实现空穴的高效传输。端位的二茂铁基团具有很强的给电子能力，有助于电子传输到分子中心的胺基官能团，增强材料的空穴传输能力，提高空穴迁移率；三苯胺的星状结构以及分子中烷基可减少分子聚集，提高材料的成膜性能，与钙钛矿层接触性良好，降低串联阻抗，减少载流子复合。改变共轭桥中噻吩环结构调控空穴材料的能级，与钙钛矿以及对电极能级相匹配。项目以二茂铁基星状空穴传输材料的设计、合成以及对空穴迁移的影响为主线，研究二茂铁基团、噻吩环等结构对星状空穴传输材料性能的影响，探讨空穴传输材料与空穴迁移率的关系及其在PSC中的作用机理。研究成果对新型空穴传输材料的开发以及高效钙钛矿太阳能电池的制备提供新思路和实验基础。

高效空穴传输材料对提高钙钛矿太阳能电池（PSC）的性能具有重要作用。本项目合成以三苯胺为核、二茂铁乙炔为端位基团、双键为共轭桥的有机空穴传输分子，作为空穴传输材料，在PSC中实现空穴的高效传输。端位的二茂铁基团具有很强的给电子能力，有助于电子传输到分子中心的胺基官能团，增强材料的空穴传输能力，提高空穴迁移率；已合成化合物空穴迁移率在1~4×10-4 cm2 V-1 s-1。三苯胺以及分子中烷基可减少分子聚集，提高材料的成膜性能，与钙钛矿层接触性良好，降低串联阻抗，减少载流子复合。改变取代基结构调控空穴材料的能级，所合成材料能与钙钛矿以及对电极能级相匹配。项目合成新型有机化合物25种，高效空穴传输材料12种，获得了高空穴迁移率的含二茂铁基空穴传输材料，制备了含二茂铁基空穴传输材料的正、反式钙钛矿太阳能电池光伏性能，在使用低浓度该类材料的条件下，分别获得了9.36 %和11.43 %的光电转换效率。研究结果揭示了该类空穴传输材料与空穴迁移率的关系及其在PSC中低浓度无掺杂的潜力。研究成果对新型空穴传输材料的开发以及高效钙钛矿太阳能电池的制备提供新思路和实验基础。