Methylammonium lead iodide (MAPI) has proven to be an exceptional light-absorber for single-junction thin-film solar cells. Nonetheless, degradation induced by environmental agents (air, moisture, heat) limits the stability of this hybrid perovskite. Here, we demonstrate that coating evaporated MAPI thin films with different hydrophobic molecules leads to a significant improvement in their stability. We especially investigated the degradation of MAPI and the subsequent formation of PbI₂ at 150 °C by in situ XRD analysis and showed that this transformation is remarkably slowed down in films coated with trioctyl phosphine oxide and tridodecyl methylammonium iodide. This enhances the processability of such films, which is an important aspect for the fabrication of thin-film devices. Eventually, we demonstrate that such protected films can be implemented in single-junction n–i–p solar cells without any loss in the device efficiency.

中文翻译：

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用有机分子涂覆蒸发的MAPI薄膜：改进的高温稳定性和在高效太阳能电池中的实现

甲基铵碘化铅（MAPI）已被证明是单结薄膜太阳能电池的杰出吸光剂。但是，由环境因素（空气，湿气，热）引起的降解限制了这种杂化钙钛矿的稳定性。在这里，我们证明了用不同的疏水分子涂覆蒸发的MAPI薄膜会导致其稳定性的显着提高。我们特别研究了MAPI的降解以及随后形成的PbI ₂在150°C下通过原位XRD分析发现，这种转变在涂有三辛基氧化膦和三十二烷基甲基碘化碘的薄膜中显着减慢了。这增强了这种膜的可加工性，这是制造薄膜器件的重要方面。最终，我们证明了这种保护膜可以在单结n–i–p太阳能电池中实现，而不会降低器件效率。