Decoupled self-assembled monolayer and perovskite deposition for efficient flexible solar modules
Yeyong Wu, Xikun Zhang, Tiankai Zhang, Guiying Xu, Yunxiu Shen, Chengxin Guo, Qing Miao, Junyuan Ding, Yue Yin, Qinrong Cheng, Wen Liu, Xiaoxiao Wu, Kaiqiang Chen, Wenwen Kou, Zhiyun Cao, Haiyang Chen, Weijie Chen, Yujin Chen, Feng Gao, Yaowen Li, Yongfang LiThe power conversion efficiency (PCE) and stability of flexible perovskite solar modules (PSMs) are less than those of their rigid devices because surface hydroxyls desorption on flexible substrates, which disrupts self-assembled monolayer (SAM) anchoring and perovskite crystallization. We developed a decoupled SAM-perovskite codeposition strategy that accelerates SAM anchoring by reducing the SAM-perovskite interaction and ameliorates perovskite crystallization. The certified PCE with phenethylammonium iodide as the passivation molecule was 20.2% on PSMs with device areas of 750 cm 2 . With 1,3-diaminopropane dihydroiodide as the passivator, the PCE of 22.0% for a device area of 14.55 cm 2 decreased by 8% after 1044 hours under maximum power point tracking at 85°C and 65% relative humidity. The devices pass all sequences of an international commercialization assessment standard for flexible portable PSMs.