无机阳离子掺杂制备的碳基钙钛矿太阳能电池及其性能研究

Carbon-based perovskite solar cells have the most potential to be used in commercialized devices due to their low cost, easy preparation, and highly scalable screen printing deposition process. But to date, the photoelectric conversion efficiency of the carbon-based device is still lag behind and their overall poor photo-stability and thermal stability have been the major factors hindering their fast commercialization. In this project, inorganic cation doping method will be used to improve the crystallization of the perovskite as well as the intrinsic stability, which is fundamental for the preparation of high efficiency and stable carbon-based perovskite solar cells. Firstly, several processing strategies will be employed to improve the quality of the hybrid cationic perovskite films, including solvent engineering and additive-assisted deposition. We will explore the deposition method of hybrid cationic perovskite in the inorganic mesoporous films. Combined with a novel n-i-p inorganic mesoporous metal oxide framework, efficient carbon-based perovskite solar cells will be constructed. Furthermore, the effects of the moisture, temperature, and light soaking on the long-term stability performance of the carbon-based perovskite solar cells will be explored. In order to obtain the hybrid cationic perovskite materials with excellent photoelectric properties and stability performance, we further address these stability issues with an investigation of the changes of the hybrid cationic perovskite materials as well as the charge transport and recombination in the aging device. This proposed project and its expected achievement will greatly promote the application of low-cost carbon-based perovskite solar cells.

碳基钙钛矿太阳能电池具有低成本、易加工，适合大规模印刷制备等优点，具有非常大的应用潜力。然而器件的光电转换效率仍然相对较低，且光热稳定性问题尚未解决。本项目利用无机阳离子掺杂提高钙钛矿晶体质量以及本征稳定性，为制备高效、稳定的碳基钙钛矿太阳能电池提供了前提。主要从两方面展开工作：首先研究溶剂工程及添加剂作用对钙钛矿膜层质量的影响，制备出高质量的杂化阳离子钙钛矿膜层，同时探索杂化阳离子钙钛矿在无机介孔膜结构中的成膜工艺，结合n-i-p无机介孔氧化物框架构筑高效率的碳基钙钛矿太阳能电池；在此基础上，研究湿度、温度、光照等因素对器件长期稳定性的影响，探索杂化阳离子钙钛矿材料以及器件内部电荷传输、复合等物理过程随老化时间的演化规律，以期获得光电性能优异、稳定的杂化阳离子钙钛矿太阳能电池材料及器件。本项研究的成果将为低成本碳基钙钛矿太阳能电池的进一步实用化奠定基础。

围绕钙钛矿薄膜的高质量制备和稳定性提升方法，从钙钛矿晶体缺陷钝化，界面优化以及锡基钙钛矿薄膜可控制备等方面开展了较为系统的研究工作，进而制备了具有较高效率的钙钛矿太阳能电池，并研究了制约器件稳定性的因素。具体研究内容总结如下：（1）提出了利用多官能团添加剂分子实现钙钛矿薄膜的多位点钝化以及结晶调控。制备的杂化阳离子钙钛矿薄膜具有减少的缺陷态密度，优化后的器件性能达到20.31%，能够在存放60天后保持初始效率的94%；（2）合成了一种聚苯乙烯磺酸钠包裹的金纳米四面体，其具有较强的局域表面等离子体共振效应，可提高钙钛矿活性层的光吸收以及改善界面电荷注入过程，优化后的器件短路电流密度相对提高了近15.4%；（3）利用高疏水大尺寸有机阳离子构建了同时改善钙钛矿结晶质量以及稳定性的锡基钙钛矿薄膜，能够显著抑制二价锡的氧化，未封装器件在600小时的氮气环境中能够保持初始效率的70%；此外，利用晶种层方法发展了具有普适性制备高质量锡基钙钛矿薄膜的工艺技术，所制备的钙钛矿薄膜具有较少的晶界，可实现结晶取向生长，制备的锡基钙钛矿太阳能电池性能达到8.54%。以上工作可用于发展稳定和非铅的碳基钙钛矿太阳能电池。