Perovskite solar cells (PSCs) have rapidly developed and achieved power conversion efficiencies of over 20% with diverse technical routes. Particularly, planar‐structured PSCs can be fabricated with low‐temperature (≤150 °C) solution‐based processes, which is energy efficient and compatible with flexible substrates. Here, the efficiency and stability of planar PSCs are enhanced by improving the interface contact between the SnO₂ electron‐transport layer (ETL) and the perovskite layer. A biological polymer (heparin potassium, HP) is introduced to regulate the arrangement of SnO₂ nanocrystals, and induce vertically aligned crystal growth of perovskites on top. Correspondingly, SnO₂–HP‐based devices can demonstrate an average efficiency of 23.03% on rigid substrates with enhanced open‐circuit voltage (V_OC) of 1.162 V and high reproducibility. Attributed to the strengthened interface binding, the devices obtain high operational stability, retaining 97% of their initial performance (power conversion efficiency, PCE > 22%) after 1000 h operation at their maximum power point under 1 sun illumination. Besides, the HP‐modified SnO₂ ETL exhibits promising potential for application in flexible and large‐area devices.

中文翻译：

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多功能聚合物调节的SnO2纳米晶体增强了界面接触，可实现高效，稳定的平面钙钛矿太阳能电池。

钙钛矿太阳能电池（PSC）迅速发展，通过多种技术路线实现了超过20％的功率转换效率。特别是，平面结构的PSC可以采用基于低温（≤150°C）的溶液工艺来制造，该工艺具有能源效率并与柔性基板兼容。在这里，通过改善SnO ₂电子传输层（ETL）与钙钛矿层之间的界面接触，可以提高平面PSC的效率和稳定性。引入生物聚合物（肝素钾，HP）来调节SnO ₂纳米晶体的排列，并在顶部诱导钙钛矿的垂直排列晶体生长。相应地，SnO ₂–基于HP的设备在具有1.162 V的增强的开路电压（V _OC）和高重现性的刚性基板上可以显示平均23.03％的效率。归因于增强的接口绑定，这些设备获得了很高的操作稳定性，在1个阳光照射下在其最大功率点运行1000 h后，仍保留了其初始性能的97％（功率转换效率，PCE> 22％）。此外，HP改良的SnO ₂ ETL在柔性和大面积设备中具有广阔的应用前景。