Microscale Confined Adhesion Strategy for Liquid Metal‐Based Highly Stretchable Bioelectrode Arrays

Abstract Liquid metal (LM), with its excellent fluidity and electrical conductivity, holds great promise in the field of flexible electronics. However, its high surface tension and poor wettability pose challenges for patterning, limiting its integration and application potential. To overcome this, a novel microscale confined adhesion strategy is proposed that leverages adhesion differences across various surfaces to achieve precise LM patterning. The resulting 16‐channel LM electrode array features fine resolution (150 µm), ultrahigh stretchability (up to 600% strain), and good durability (2 × 10 4 cycles at 100% strain). Moreover, the adhesion strength between the encapsulation layer and the substrate at recording sites is critical for maintaining electrode stability under mechanical stress. To enhance this adhesion, an encapsulation material named “BAE” is synthesized, in which disulfide bonds can react with thiol‐modified substrates to improve interfacial adhesion strength (243 kPa, 2.3 times higher than the unmodified control) and mechanical stability. Additionally, polypyrrole is vapor‐deposited onto BAE to enhance the signal transmission quality of the electrode and enable efficient coupling with electromyographic signals. The stretchable electrode array reliably records multi‐channel electrophysiological signals under dynamic conditions and achieves 93% gesture recognition accuracy using deep learning, providing support for the development of health monitoring and intelligent control systems.