Nacre‐Inspired Coordination Networks for Transparent, Ultra‐Stable Polyimide Films in Flexible Electronics
Yanyu Gao, Yan Sui, Ziyang Liu, Zhe Tang, Xinyu Zeng, Xiao Su, Cheng Wang, Qianqian Yu, Linge Wang
Abstract
Abstract The development of high‐performance colorless polyimides (CPIs) demands a paradigm shift to overcome the mutual exclusivity of optical transparency, thermal stability, and mechanical strength. Drawing inspiration from nacre's hierarchical coordination motifs, a biomimetic strategy is presented that integrates molecular engineering with Zn 2+ ‐mediated crosslinking. Six pyridine‐containing diamines are synthesized to suppress charge transfer complexes and copolymerized with 6FDA, forming tunable polyimide backbones. Subsequent Zn 2 ⁺ coordination generates a dynamic N─Zn─N network, which rigidifies chains and delivers synergistic enhancements: an excellent T g of 338.5 °C (+16.6%), ultralow charge transfer complexes of 45.8 ppm K⁻¹ (−20.6%), and tensile strength of 138 MPa (+46.8%) while retaining 89.3% transmittance. The film enable cytocompatible wearable sensors with 38 ms response times and stable signal output after 10 000 bending cycles. Moreover, its relevance to foldable ACEL devices highlights the potential for industrial scalability. This work reimagines CPI design through coordination chemistry, offering a blueprint for multifunctional polymers in next‐generation electronics.