The composite electron transporting layer (ETL) of metal oxide with [6,6]-phenyl-C₆₁-butyric acid methyl ester (PCBM) prevents perovskite from metal electrode erosion and increases p–i–n perovskite solar cell (PVSC) stability. Although the oxide exhibits protective function, an additional work function modifier is still needed for good device performance. Usually, complicated multistep synthesis is employed to have a highly crystalline film that increases manufacturing cost and inhibits scalability. We report a facile synthesis of a novel organic-molecule-capped metal oxide nanoparticle film for the composite ETL. The nanoparticle film not only has a dual function of electron transport and protection but also exhibits work function tunability. Solvothermal-prepared SnO₂ nanoparticles are capped with tetrabutylammonium hydroxide (TBAOH) through ligand exchange. The resulting TBAOH–SnO₂ nanoparticles disperse well in ethanol and form a uniform film on PCBM. The power conversion efficiency of the device dramatically increases from 14.91 to 18.77% using this layer because of reduced charge accumulation and aligned band structure. The PVSC thermal stability is significantly enhanced by adopting this layer, which prevents migration of I^– and Ag. The ligand exchange method extends to other metal oxides, such as TiO₂, ITO, and CeO₂, demonstrating its broad applicability. These results provide a cornerstone for large-scale manufacture of high-performance and stable PVSCs.

中文翻译：

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高效且稳定的PIN钙钛矿型太阳能电池分子封端金属氧化物的功函可调谐电子传输层。

具有[6,6]-苯基-C _61-丁酸甲酯（PCBM ）的金属氧化物的复合电子传输层（ETL）可以防止钙钛矿受到金属电极的腐蚀，并增加p–i–n钙钛矿太阳能电池（PVSC）的稳定性。尽管氧化物具有保护功能，但仍需要额外的功函数改性剂以实现良好的器件性能。通常，采用复杂的多步合成来获得高度结晶的膜，从而增加制造成本并抑制可扩展性。我们报告了用于复合ETL的新型有机分子封端的金属氧化物纳米颗粒薄膜的简便合成。纳米颗粒膜不仅具有电子传输和保护的双重功能，而且还表现出功函数可调性。溶剂热法制备的SnO ₂纳米粒子通过配体交换被氢氧化四丁铵（TBAOH）封端。所得的TBAOH-SnO ₂纳米颗粒在乙醇中分散良好，并在PCBM上形成均匀的膜。使用此层，由于减少了电荷积累和排列的能带结构，器件的功率转换效率从14.91％大幅提高到18.77％。所述PVSC热稳定性通过采用该层，从而防止迁移我显著增强^-和Ag。配体交换方法扩展到其他金属氧化物，例如TiO ₂，ITO和CeO ₂，证明了其广泛的适用性。这些结果为大规模生产高性能和稳定的PVSC提供了基础。