Zhao Jinbo, Su Zhenhuang, Pascual Jorge, Wu Hongzhuo, Wang Haibin, Aldamasy Mahmoud H, Zhou Zhengji, Wang Chenyue, Li Guixiang, Li Zhe, Gao Xingyu, Hsu Chain-Shu, Li Meng
Key Lab for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-Efficiency Display and Lighting Technology, School of Nanoscience and Materials Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng, 475004, P. R. China.
Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Advanced Research Institute, Chinese Academy of Sciences, 239 Zhangheng Road, Shanghai, 201204, P. R. China.
Adv Mater. 2024 Sep;36(36):e2406246. doi: 10.1002/adma.202406246. Epub 2024 Jul 20.
Mixed tin-lead (Sn-Pb) perovskites have attracted the attention of the community due to their narrow bandgap, ideal for photovoltaic applications, especially tandem solar cells. However, the oxidation and rapid crystallization of Sn and the interfacial traps hinder their development. Here, cross-linkable [6,6]-phenyl-C-butyric styryl dendron ester (C-PCBSD) is introduced during the quenching step of perovskite thin film processing to suppress the generation of surface defects at the electron transport layer interface and improve the bulk crystallinity. The C-PCBSD has strong coordination ability with Sn and Pb perovskite precursors, which retards the crystallization process, suppresses the oxidation of Sn, and improves the perovskite bulk and surface crystallinity, yielding films with reduced nonradiative recombination and enhanced interface charge extraction. Besides, the C-PCBSD network deposited on the perovskite surface displays superior hydrophobicity and oxygen resistance. Consequently, the devices with C-PCBSD obtain PCEs of up to 23.4% and retained 97% of initial efficiency after 2000 h of storage in a N atmosphere.
混合锡铅（Sn-Pb）钙钛矿因其窄带隙而受到学界关注，这对于光伏应用，特别是串联太阳能电池来说非常理想。然而，Sn的氧化和快速结晶以及界面陷阱阻碍了它们的发展。在此，在钙钛矿薄膜制备的猝灭步骤中引入可交联的[6,6]-苯基-C-丁酸苯乙烯基树枝状酯（C-PCBSD），以抑制电子传输层界面处表面缺陷的产生并提高整体结晶度。C-PCBSD与Sn和Pb钙钛矿前驱体具有很强的配位能力，这延缓了结晶过程，抑制了Sn的氧化，并提高了钙钛矿整体和表面的结晶度，从而得到具有减少的非辐射复合和增强的界面电荷提取的薄膜。此外，沉积在钙钛矿表面的C-PCBSD网络表现出优异的疏水性和耐氧性。因此，具有C-PCBSD的器件获得了高达23.4%的功率转换效率（PCE），并且在N气氛中储存2000小时后仍保留了初始效率的97%。
