For practical use of perovskite solar cells (PSCs) the instability issues of devices, attributed to degradation of perovskite molecules by moisture, ions migration, and thermal‐ and light‐instability, have to be solved. Herein, highly efficient and stable PSCs based on perovskite/Ag‐reduced graphene oxide (Ag‐rGO) and mesoporous Al₂O₃/graphene (mp‐AG) composites are reported. The mp‐AG composite is conductive with one‐order of magnitude higher mobility than mp‐TiO₂ and used for electron transport layer (ETL). Compared to the mp‐TiO₂ ETL based cells, the champion device based on perovskite/Ag‐rGO and SrTiO₃/mp‐AG composites shows overall a best performance (i.e., V_OC = 1.057 V, J_SC = 25.75 mA cm⁻², fill factor (FF) = 75.63%, and power conversion efficiency (PCE) = 20.58%). More importantly, the champion device without encapsulation exhibits not only remarkable thermal‐ and photostability but also long‐term stability, retaining 97–99% of the initial values of photovoltaic parameters and sustaining ≈93% of initial PCE over 300 d under ambient conditions.

中文翻译：

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SrTiO3 / Al2O3石墨烯电子传输层，用于高效稳定且高效的基于复合材料的钙钛矿太阳能电池，效率为20.6％

对于钙钛矿太阳能电池（PSC）的实际使用，必须解决由于水分，离子迁移以及热和光不稳定性而导致的钙钛矿分子降解所造成的设备不稳定性问题。本文报道了基于钙钛矿/ Ag还原氧化石墨烯（Ag-rGO）和中孔Al ₂ O ₃ /石墨烯（mp-AG）复合材料的高效稳定的PSC 。mp-AG复合材料的导电性比mp-TiO ₂高一个数量级，并用于电子传输层（ETL）。与基于mp‐TiO ₂ ETL的电池相比，基于钙钛矿/ Ag‐rGO和SrTiO ₃ / mp‐AG复合材料的冠军设备显示出总体最佳性能（即V _OC= 1.057 V，J _SC = 25.75 mA cm ^-2，填充系数（FF）= 75.63％，功率转换效率（PCE）= 20.58％）。更重要的是，没有封装的冠军设备不仅具有出色的热稳定性和光稳定性，而且还具有长期稳定性，在环境条件下300 d内可保持97-99％的光伏参数初始值，并维持约93％的初始PCE。