Biomimetic Janus Eutectogels With Dynamic Compliance for High‐Fidelity Bioelectronic Interfaces

The recording of high‐fidelity electrophysiological signals is the cornerstone of bioelectronics development. However, overcoming signal interference caused by motion artifacts and unintended adhesion during daily activities remains a challenge. This paper introduces a biomimetic Janus eutectogels with dynamic compliance, in which the adhesive matrix contains hierarchical physical interactions composed of hydrogen bonds and ion‐dipole interactions, allowing the polymer network to remain in a gel point state where viscosity and elasticity are nearly equivalent within the deformation frequency range of human skin (0.01‐100 Hz). The anti‐adhesive top surface at the nanoscale is formed by the self‐aggregation of amphiphilic polyhedral oligomeric silsesquioxane (POSS) acting as a giant surfactant at the liquid‐air interface. The adhesion strength difference between the top and bottom surfaces reaches up to 52‐fold. The eutectogel can avoid signal interference induced by motion artifacts and unintended adhesion under various physiological conditions, enabling high‐fidelity acquisition of diverse electrophysiological signals (including electromyography, electrocardiography, and electroencephalography). We further integrated device integration and deep learning technology to construct an intelligent motion monitoring system, which conducts hierarchical evaluation of motion states and achieves a classification accuracy of up to 92.4%, demonstrating the potential of the material for physiological monitoring in real‐world motion scenarios.