Since Yan's work, incorporation of some lanthanide elements, such as Eu and Nd, into MAPbI₃ layer has been proven to be a powerful strategy on improving the permanence of the perovskite solar cells (PSCs). However, a comprehensive configuration has not been given for different lanthanide elements doping while the mechanism has not been clarified. Herein, the incorporation of various lanthanides ions (Ln³⁺ = Ce³⁺, Eu³⁺, Nd³⁺, Sm³⁺, or Yb³⁺) into perovskite films to largely enhance the performance of PSCs is presented. Arising from the enlarged grain size and crystallinity of perovskite film upon Ln³⁺ ions doping, the efficiency and stability of PSCs are significantly improved. Extraordinarily, PSCs with Ce³⁺ doping achieve the best performance, with a champion power conversion efficiency (PCE) of 21.67% in contrast to 18.50% for pristine PSCs, and outstanding long‐term and UV irradiation stability. Such high performance of PSCs after Ce³⁺ doping originates from special Ce³⁺/Ce⁴⁺ redox pair and the unique 4f‐5d absorption in the UV region. Finally, the flexible PSCs with low‐temperature preparation are explored. Considering the richer deposition of cerium element in the earth and lower price, the findings may provide new opportunities for developing low‐cost, highly efficient, air/UV stable, and flexible PSCs.

中文翻译：

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将镧系元素离子掺入钙钛矿薄膜中，以实现高效，稳定的钙钛矿太阳能电池。

自Yan开展工作以来，已证明将某些镧系元素（例如Eu和Nd）掺入MAPbI ₃层是提高钙钛矿太阳能电池（PSC）持久性的有效策略。但是，还没有针对不同的镧系元素掺杂给出全面的配置，但机理尚未阐明。在此，提出了将各种镧系离子（Ln ³⁺ ＝ Ce ³⁺，Eu ³⁺，Nd ³⁺，Sm ³⁺或Yb ³⁺）掺入钙钛矿膜中以大大增强PSC的性能。Ln ³⁺上钙钛矿薄膜的增大晶粒尺寸和结晶度引起离子掺杂后，PSC的效率和稳定性得到了显着提高。尤其是，掺杂Ce ^3+的PSC达到最佳性能，其原始功率转换效率（PCE）为21.67％，而原始PSC的功率转换效率为18.50％，并且具有出色的长期和紫外线照射稳定性。Ce ³⁺掺杂后的PSC如此出色的性能源于特殊的Ce ³⁺ / Ce ⁴⁺氧化还原对和紫外线区域中独特的4f-5d吸收。最后，探讨了低温制备的柔性PSC。考虑到地球上铈元素的丰富沉积和较低的价格，这些发现可能为开发低成本，高效，空气/紫外线稳定和灵活的PSC提供了新的机会。