新型无LiTFSI掺杂的Spiro型空穴传输材料的合成及其在钙钛矿太阳能电池中性能研究

空穴传输材料对钙钛矿太阳能电池的效率、稳定性以及制作成本具有重要的影响。迄今为止，Spiro-OMeTAD是使用最广泛、效率最高和最有希望大规模商业化的空穴传输材料，然而其合成复杂、价格昂贵，且空穴迁移率较低，需掺杂LiTFSI来提高迁移率，而LiTFSI会导致电池稳定性下降。针对上述问题，本项目拟运用简易的新方法来合成Spiro-OMeTAD，降低其价格; 在Spiro-OMeTAD螺二芴优势结构的基础上，通过增大分子共轭体系来合成具有高空穴迁移率的Spiro型空穴传输材料，利用空穴传输材料双阳离子盐代替LiTFSI来掺杂空穴传输材料，应用在钙钛矿太阳能电池中进一步提高电池的效率和稳定性,同时研究并阐明材料分子结构-性能的构效关系以及钙钛矿与空穴传输材料界面的相互作用机理。本研究能为将来高效空穴传输材料的设计提供理论指导以及钙钛矿太阳能电池商业化奠定基础。

Hole transport materials (HTMs) have a great influence on the power conversion efficiency, long-term stability and production cost of perovskite solar cells (PSCs). To date, Spiro-OMeTAD has been the most commonly used, efficient and promising large-scale commercial HTM in PSCs. However, it suffers from tedious synthesis and high-cost, moreover, Spiro-OMeTAD exhibits low hole-mobility in pristine form which can be enhanced by the addition of LiTFSI. Unfortunately, LiTFSI negatively influences the stability of PSCs device. In this proposal, Spiro-OMeTAD will be synthesized via a new facile synthesis method, lowering its production cost. On the basis of the excellent spirobifluorene-based core structure of Spiro-OMeTAD，new spiro-based HTMs with high hole-mobility will be synthesized by increasing the molecular π-conjugation system. Moreover, a dicationic salt of spiro-based HTM instead of LiTFSI will be employed as an effective p-dopant to dope the HTM. The performance and stability of PSCs are expected to be further improved. At the same time, the structure-activity relationship and working mechanism of the interface between perovskite and HTM in PSCs will be well investigated and clarified. The results of this project are expected to provide important theoretical guidance for designing highly efficient hole transport materials and lay a foundation for the commercialization of perovskite solar cells in the future.