Authors: Tianxiao Liu, Zhijun Ren, Yangyang Liu, Yaoyao Zhang, Jing Liang, Fangwen Cheng, Yiran Li, Xiaoyu Shi, Yunjie Dou, Xiaodong Hu, Lingyuan Wang, Siwei Luo, Feifei Wang, Xiaoxiao Peng, Yu Zhao, Wei Wang, Yi Cao, Feng Gao, Shangshang Chen
Published: 2025-05-28
Source: Full article
Ultraviolet (UV) radiation poses a substantial challenge to the stability of prevalent p-i-n (positive-intrinsic-negative) perovskite solar cells (PSCs), demanding more robust hole-transport layers (HTLs) due to light incident from the HTL side. Here, we unveil that commonly used self-assembled monolayer (SAM)–type HTLs suffer from poor UV stability that causes irreversible damage to hole extraction and impairs device stability. To address this issue, we develop a polymeric and UV-stable HTL named Poly-2PACz, which exhibits strong binding to substrates and exceptional UV resistance over SAM-type HTLs. The PSCs blade-coated under ambient conditions using Poly-2PACz HTL achieved a remarkable efficiency of 26.0% and outstanding UV stability. Our cells retain 80% of the initial PCE even after about 500 hours of high-intensity UV illumination [7.7 times higher than that of air mass 1.5 global (AM 1.5G) solar spectrum]. Furthermore, Poly-2PACz exhibits good wettability and high conductance, enabling the fabrication of blade-coated minimodules with an aperture efficiency of 22.2% and excellent uniformity.