Synergistic substrate-interface regulation via fluorinated bacterial cellulose and dual-network for durable liquid metal electronics

Construct a dual-network structure to achieve a leap in substrate performance • Fluorinated cellulose adaptively tunes the liquid-metal (LM) interface, enabling ultra-durable printed electronic devices. • Excellent sensing performance and diverse applications Liquid metals (LMs) are promising for printed electronics, but their durability is limited by weak substrates and LM oxidation/leakage. Here, we propose a dual strategy combining aqueous polyurethane (WPU) substrate regulation and LM interface optimization. By introducing dimethylglyoxime (DMG) and Zn 2+ , a dual-network structure with multiple hydrogen bonds and metal-ligand coordination bonds is formed, enabling the WPU-Zn substrate to achieve a tensile strength of 21.6 MPa, an elongation at break of 1000%, and a self-healing efficiency of 98.3% after 24 h at room temperature. Fluorinated bacterial cellulose (FBC) is further prepared to mediate the WPU-Zn/LM interaction via adaptive dipole-dipole forces, endowing the system with excellent tensile stability and environmental durability. Using DIW 3D printing, flexible printed electronic devices are fabricated; the serpentine sensor shows a stable linear response (GF = 0.3, R 2  = 0.98), fast response/recovery times (196.8/246.8 ms), and durability over 2000 cycles, achieving 98.6% gesture-recognition accuracy in human-machine interaction. A customized electrode patch retains 95% of ECG signal amplitude after 12 h of monitoring, clearly outperforming commercial gel electrodes. This work provides a comprehensive solution for durable LM printed electronics, facilitating large-scale manufacturing and commercialization for wearable and biomedical applications.