有机无机杂化钙钛矿太阳能电池是新一代光伏发电技术的典型代表，利用透明导电氧化物（Transparent conductive oxide, TCO）具有高光透过性和高电导率的特点，还可以制备半透明电池及高效率叠层电池来进一步拓宽器件应用场景。然而，现有研究对TCO作为顶电极材料在钙钛矿太阳能电池中的应用还不够系统深入，特别是其在光电转换效率、稳定性、多应用场景等方面还有显著的提升空间和科学研究价值。因此，研究立足于TCO材料特性，深入探索其在抑制器件离子迁移、提升电池偏压稳定性、制备高性能半透明电池及柔性半透明电池等方面的重要作用，主要的研究内容和创新性成果如下：首先，本文研究并揭示了基于廉价金属（例如铜）电极的器件效率低、稳定性差的原因，提出了一种TCO+廉价金属的复合电极策略用于提升正式结构电池的光电性能。TCO能有效抑制钙钛矿电池中的离子迁移，阻止金属电极与钙钛矿之间的化学反应，进而提升器件的光电转化效率和稳定性。因此基于复合电极的FAPbI3器件，获得了23.7%（认证23.2%）的光电转化效率，且该器件在正向偏压、反向偏压，最大功率点追踪等测试下均表现出了优异的稳定性。同时该复合电极策略还可以拓展用于不同TCO材料与廉价金属的组合。接着，利用TCO材料的高透光性，通过飞秒超快反射光谱等先进表征手段，研究了完整半透明器件中的光生空穴抽取及传输过程。发现钙钛矿/空穴传输层的界面缺陷及非辐射复合损失，是制约半透明器件性能提升的关键。使用2-氯代苯乙胺氢碘酸盐材料对钙钛矿/空穴传输层界面进行界面缺陷钝化，可有效抑制界面复合形成二维钙钛矿，提升器件稳定性。最终Cs0.05FA0.95PbI3体系的半透明钙钛矿电池获得了23.3%（认证22.3%）的效率，与商用的PERC电池构建四端叠层太阳能电池获得了30.8 mW cm–2的输出功率。最后，针对柔性半透明钙钛矿太阳能电池的电极弯折稳定性、高透光性以及器件高效率等方面开展了深入研究。制备了超薄氧化铟锌（IZO）薄膜作为柔性器件的顶电极，有效解决了电极的弯折稳定性问题。同时提出了新戊胺氢碘酸盐对钙钛矿/电子传输层的埋底界面进行钝化处理策略，进一步降低界面复合损失，提升器件光电性能。所制备的Cs0.05FA0.95PbI3体系柔性半透明钙钛矿太阳能电池获得了16.8%的光电转化效率和近红外光区域超过70%的透光率。
Organic-inorganic hybrid perovskite solar cells (PSCs) represents the next generation of photovoltaic technology. Transparent conductive oxide (TCO) has high light transmittance and good conductivity, and can be applied to semi-transparent and tandem solar cells as transparent electrode. However, the existing researches on TCO transparent electrode is not systematic. The power conversion efficiency, device stability, and application scenarios still need further improvement. The research takes advantage of the characteristics of TCO materials and explores their applications in the field of perovskite solar cells. The research investigates the role of TCO including mitigating ion migration, enhancing cell bias voltage stability, and producing for high-performance semi-transparent and flexible semi-transparent perovskite solar cells. The specific research contributions are outlined as follows:Firstly, investigating the origin of the low efficiency and poor stability of devices based on low-cost metal electrodes (e.g., copper). A composite electrode structure combining transparent conductive oxides with inexpensive metals was proposed to improve the optoelectronic performance with the n-i-p device structure. TCO effectively suppresses ion migration in perovskite cells, preventing chemical reactions between metal electrode and perovskite film, thereby enhancing the device's power conversion efficiency and stability. The resulting copper electrode-based FAPbI3 device achieved a power conversion efficiency of 23.7% (certified 23.2%), exhibiting excellent stability under forward bias, reverse bias, and maximum power point tracking. This composite electrode process can be extended to various combinations of TCO materials and inexpensive metals.Then, utilizing the high transparency characteristic of TCO materials to fabricate semi-transparent perovskite solar cells. Advanced characterizations including femtosecond ultrafast reflectance spectroscopy were employed to characterize the photogenerated hole extraction and transfer dynamics in complete working devices. Defects and non-radiative recombination losses at the perovskite/hole transport layer interface were identified as an important factor limiting the performance of semi-transparent devices. Post-treatment the perovskite/hole transport layer interface with 2-chloroethylamine effectively passivated interface defects, suppressed interface recombination, and enhanced stability, resulting in Cs0.05FA0.95PbI3 semitransparent perovskite cell with a 23.3% (certified 22.3%) efficiency. Additionally, a four-terminal tandem solar cell using commercial PERC cell was conducted and achieved an output power of 30.8 mW cm–2.Finally, in-depth research was conducted on the electrode bending stability, high transparency, and device efficiency of flexible semitransparent perovskite solar cells. Ultra thin IZO layer was prepared as the top electrode of flexible devices, and effectively improved the bending stability of the transparent electrode without sacrificing conductivity. Combined with the treatment of the perovskite/electron transport layer interface with the novel neopentylamine hydroiodide, interface recombination losses were further suppressed. The corresponding Cs0.05FA0.95PbI3 flexible semitransparent perovskite solar cells achieved a power conversion efficiency of 16.8% and a transmittance of over 70% in the near-infrared region.
