苏州大学李永舫研究团队报了应变调节延缓钙钛矿太阳能电池的自然运行衰变。相关研究成果于2024年10月14日发表在国际顶尖学术期刊《自然》。

钙钛矿太阳能电池（pero-SCs）在过去十年中经历了快速发展。然而，目前还缺乏系统的研究，来调查硅太阳能电池中使用的工作寿命评估经验规则是否可以应用于pero-SCs。人们普遍认为，由于在黑暗中的自愈效应，pero-SCs在昼夜循环下表现出增强的稳定性。研究虽然发现高效FAPbI₃ pero-SCs的降解实际上在自然昼夜循环模式下要快得多，但对基于连续模式测试估算pero-SCs工作寿命的广泛接受的方法提出了质疑。

该文中，研究人员揭示了关键因素是，钙钛矿在操作过程中热膨胀/收缩引起的晶格应变，这种效应在连续照明模式下逐渐松弛，但在循环模式下同步循环。

循环模式下的周期性晶格应变，导致操作过程中的深阱积累和化学降解，降低了离子迁移电位，从而缩短了器件寿命。研究人员引入苯基硒酰氯（Ph-Se-Cl），来调节钙钛矿在日夜循环过程中的晶格应变。修改后的循环模式中，其效率达到26.3%，T80寿命提高了10倍。

附：英文原文

Title: Strain regulation retards natural operation decay of perovskite solar cells

Author: Shen, Yunxiu, Zhang, Tiankai, Xu, Guiying, Steele, Julian A., Chen, Xiankai, Chen, Weijie, Zheng, Guanhaojie, Li, Jiajia, Guo, Boyu, Yang, Heyi, Wu, Yeyong, Lin, Xia, Alshahrani, Thamraa, Yin, Wanjian, Zhu, Jian, Wang, Feng, Amassian, Aram, Gao, Xingyu, Zhang, Xiaohong, Gao, Feng, Li, Yaowen, Li, Yongfang

Issue&Volume: 2024-10-14

Abstract: Perovskite solar cells (pero-SCs) have undergone a rapid development in the last decade. However, there is still a lack of systematic studies to investigate whether the empirical rules of working lifetime assessment used in silicon solar cells can be applied to pero-SCs. It is commonly believed that pero-SCs show enhanced stability under day/night cycling due to the reported self-healing effect in the dark.1,2 While we discovered that the degradation of highly efficient FAPbI3 pero-SCs is in fact much faster under natural day/night cycling mode, questioning the widely accepted approach to estimate the operational lifetime of pero-SCs based on continuous mode testing. We reveal the key factor to be the lattice strain caused by thermal expansion/shrinking of the perovskite during the operation, an effect that gradually relaxes under the continuous-illumination mode but cycles synchronously under the cycling mode.3,4 The periodic lattice strain under the cycling mode results in deep trap accumulation and chemical degradation during operation, decreasing the ion migration potential and hence the device lifetime.5 We introduce phenylselenenyl chloride (Ph-Se-Cl) to regulate the perovskite lattice strain during day/night cycling, which achieved the certified efficiency of 26.3% and a 10-time improved T80 lifetime under the cycling mode after the modification.

DOI: 10.1038/s41586-024-08161-x

Source: https://www.nature.com/articles/s41586-024-08161-x