Fu Shiqiang, Li Guang, Zhou Shun, Wang Jiahao, Pu Dexin, Huang Lishuai, Yu Zhiqiu, Chen Wanping, Fang Guojia, Ke Weijun
Key Lab of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China.
Key Lab of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China.
Sci Bull (Beijing). 2025 Jun 15;70(11):1786-1792. doi: 10.1016/j.scib.2025.04.017. Epub 2025 Apr 7.
All-perovskite tandem solar cells present immense potential due to their exceptional performance and versatility. However, their practical implementation is impeded by significant challenges, particularly in large-area devices, where interfacial inhomogeneities in wide-bandgap (WBG) perovskite subcells lead to high open-circuit voltage losses and low fill factors. Here, we introduce a synergistic bimolecular corroding-healing passivation strategy to enhance WBG perovskite films' passivation and interfacial uniformity. Unlike conventional passivation methods relying on halide ammonium salts, this approach directly employs precursor diamines to passivate interfacial defects, suppress recombination, and crucially induce mild surface corrosion, creating random openings on the perovskite surface. Paired molecules of piperazinium iodide then penetrate these openings, enabling deeper defect passivation and surface healing to form a smooth, homogeneous interface. This strategy enabled 1.78 eV WBG perovskite solar cells to achieve a power conversion efficiency (PCE) of 20.47% with an ultrahigh fill factor of 85.10%. Furthermore, when integrated with narrow-bandgap perovskite subcells, the fabricated all-perovskite tandem solar cells delivered PCEs of 28.36% (0.07 cm) and 27.52% (1.02 cm). This dual-molecular erosion-healing passivation strategy offers an effective and scalable solution to optimize the perovskite interface, driving advancements in the performance and manufacturability of WBG perovskite and tandem solar cells.
全钙钛矿串联太阳能电池因其卓越的性能和多功能性而展现出巨大潜力。然而，它们的实际应用受到重大挑战的阻碍，特别是在大面积器件中，宽带隙（WBG）钙钛矿子电池中的界面不均匀性会导致高开路电压损失和低填充因子。在此，我们引入一种协同双分子腐蚀-修复钝化策略，以增强WBG钙钛矿薄膜的钝化和界面均匀性。与依赖卤化铵盐的传统钝化方法不同，该方法直接使用前驱二胺来钝化界面缺陷、抑制复合，并关键地诱导温和的表面腐蚀，在钙钛矿表面形成随机开口。然后，碘化哌嗪鎓的配对分子穿透这些开口，实现更深层次的缺陷钝化和表面修复，以形成光滑、均匀的界面。该策略使1.78 eV的WBG钙钛矿太阳能电池实现了20.47%的功率转换效率（PCE），填充因子高达85.10%。此外，当与窄带隙钙钛矿子电池集成时，所制备的全钙钛矿串联太阳能电池的PCE分别为28.36%（0.07 cm²）和27.52%（1.02 cm²）。这种双分子腐蚀-修复钝化策略为优化钙钛矿界面提供了一种有效且可扩展的解决方案，推动了WBG钙钛矿和串联太阳能电池在性能和可制造性方面的进步。
