Hybrid tin‐lead (Sn‐Pb) perovskites have garnered increasing attention due to their crucial role in all‐perovskite tandem cells for surpassing the efficiency limit of single‐junction solar cells. However, the easy oxidation of Sn2+ and fast crystallization of Sn‐based perovskite present significant challenges for achieving high‐quality hybrid Sn‐Pb perovskite films, thereby limiting the device's performance and stability. Herein, an all‐in‐one additive, 2‐amino‐3‐mercaptopropanoic acid hydrochloride (AMPH) is proposed, which can function as a reducing agent to suppress the formation of Sn4+ throughout the film preparation. Furthermore, the strong binding between AMPH and Sn‐based precursor significantly slows down the crystallization process, resulting in a high‐quality film with enhanced crystallinity. The remaining AMPH and its oxidation products within the film contribute to improves oxidation resistance and a substantial reduction in defect density, specifically Sn vacancies. Benefiting from the multifunctionalities of AMPH, a power conversion efficiency (PCE) of 23.07% is achieved for single‐junction narrow‐bandgap perovskite solar cells. The best‐performing monolithic all‐perovskite tandem cell also exhibits a PCE of 28.73% (certified 27.83%), which is among the highest efficiency reported yet. The tandem devices can also retain over 85% of their initial efficiencies after 500 hours of continuous operation at the maximum power point under one‐sun illumination.

中文翻译：

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All-In‐One 添加剂为单片全钙钛矿叠层太阳能电池实现高效稳定的窄带隙钙钛矿


杂化锡铅 （Sn-Pb） 钙钛矿因其在全钙钛矿叠层电池中超越单结太阳能电池效率极限的关键作用而受到越来越多的关注。然而，Sn2+ 的易氧化和 Sn 基钙钛矿的快速结晶为实现高质量的混合 Sn-Pb 钙钛矿薄膜带来了重大挑战，从而限制了器件的性能和稳定性。在此，提出了一种多合一添加剂，2-氨基-3-巯基丙酸盐酸盐 （AMPH），它可以作为还原剂，在整个薄膜制备过程中抑制 Sn4+ 的形成。此外，AMPH 和 Sn 基前驱体之间的强结合显着减慢了结晶过程，从而产生结晶度增强的高质量薄膜。薄膜中剩余的 AMPH 及其氧化产物有助于提高抗氧化性和显著降低缺陷密度，特别是 Sn 空位。得益于 AMPH 的多功能性，单结窄带隙钙钛矿太阳能电池的功率转换效率 （PCE） 达到 23.07%。性能最好的单片全钙钛矿串联电池的 PCE 也为 28.73%（认证 27.83%），这是迄今为止报道的最高效率之一。在单太阳照明下，在最大功率点连续运行 500 小时后，串联设备还可以保持其 85% 以上的初始效率。