以CuSCN为空穴传输层的大面积高效率的钙钛矿太阳能电池

Solar cells based on organic-Inorganic perovskite, a type of potential solar cells of low-cost and high efficiency, have made significant progress. In this proposal, perovskite solar cells with inverted structure would be designed and fabricated, where a p-type semiconductor CuSCN film would be deposited electrochemically as a hole transporting layer. It will be investigated in details that how the morphology, crystallinity, transparency and conductivity of CuSCN film depend on the preparation condition such as the concentration of the precursor, the temperature of the solution bath, etc. Especially, by exposing CuSCN film to Cl2, Br2 and (SCN)2, it is expected that the conductivity of CuSCN film would enhanced by more than 100 times. Based on such investigation, it is anticipated that CuSCN film with high compactness, uniformity, transparency and conductivity would be prepared. On top CuSCN film, perovskite film with high uniformity, compactness and crystallinity would be prepared with the optimized condition. Specifically, how the fabrication process of CuSCN and perovskite films interact with each other and the effect of the interfacial structure and properties of the two films on charge separation and charge recombination at the interface would be examined in details. With the guidance of the knowledge learned above, solar cells with low cost, large area and high efficiency would be prepared, which will also lay the ground for the rational design of perovskite solar cells in the future.

基于有机-无机复合钙钛矿材料的太阳能电池，作为一种潜在的廉价高效率太阳能电池，得到了快速发展。本项目将采用倒置结构构建太阳能电池，通过电化学沉积可控制备无机空穴传输层CuSCN薄膜，详细探索制备条件如前驱体离子浓度、温度等对CuSCN薄膜形貌、结晶度、透光率及导电性的影响，尤其通过Cl2、Br2及类卤素(SCN)2参杂提高CuSCN薄膜导电性100倍以上，从而制备出高致密性、高均一、高透光率及高导电性的p型半导体材料。在CuSCN薄膜之上,优化钙钛矿材料的制备工艺，制备出具有高度均一性、致密性和结晶度的钙钛矿薄膜，重点研究CuSCN及钙钛矿材料制备过程的相互影响机制，以及界面结构及性质对界面电荷分离及复合动力学的影响。以此为指导，最终制备出大面积、低成本、高效率的钙钛矿太阳能电池，并且为未来理性设计钙钛矿太阳能电池奠定基础。

有机-无机杂化钙钛矿太阳能电池（PSCs）已经实现了前所未有的高的转化效率，其在商业应用上具有极大的潜力。然而，在杂化钙钛矿晶体结构中，易挥发的有机组分不利于其长期热稳定性。最近几年，全无机铯铅卤化物钙钛矿（CsPbX3）材料由于其优异的光电性能和良好的热稳定性而引起广泛关注，有望解决传统杂化钙钛矿电池稳定性差的问题。在所有无机钙钛矿材料中， CsPbI3具有最合适的带隙和极好的化学稳定性。然而，由于CsPbI3本身不理想的耐受因子，其仍存在相变、薄膜质量差以及低光伏性能的问题。在本文中，我们采用2D结构诱导以形成均匀高质量3D结构CsPbI3薄膜，并将其应用于太阳能电池的光吸收层以制备高性能的光伏器件。另外，由于Br−的存在，会延缓晶体的降解过程，因此我们制备了CsPbI2Br薄膜。在钙钛矿前驱液中，DMSO的加入克服了PbBr2的溶解极限，减缓了晶体的结晶速度，形成了致密、均匀的高质量钙钛矿薄膜，并将其应用于光伏器件中制备高性能太阳能电池。