Kirigami‐Structured, Low‐Impedance, and Skin‐Conformal Electronics for Long‐Term Biopotential Monitoring and Human–Machine Interfaces

Abstract

Epidermal dry electrodes with high skin‐compliant stretchability, low bioelectric interfacial impedance, and long‐term reliability are crucial for biopotential signal recording and human–machine interaction. However, incorporating these essential characteristics into dry electrodes remains a challenge. Here, a skin‐conformal dry electrode is developed by encapsulating kirigami‐structured poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/polyvinyl alcohol (PVA)/silver nanowires (Ag NWs) film with ultrathin polyurethane (PU) tape. This Kirigami‐structured PEDOT:PSS/PVA/Ag NWs/PU epidermal electrode exhibits a low sheet resistance (≈3.9 Ω sq−1), large skin‐compliant stretchability (>100%), low interfacial impedance (≈27.41 kΩ at 100 Hz and ≈59.76 kΩ at 10 Hz), and sufficient mechanoelectrical stability. This enhanced performance is attributed to the synergistic effects of ionic/electronic current from PEDOT:PSS/Ag NWs dual conductive network, Kirigami structure, and unique encapsulation. Compared with the existing dry electrodes or standard gel electrodes, the as‐prepared electrodes possess lower interfacial impedance and noise in various conditions (e.g., sweat, wet, and movement), indicating superior water/motion‐interference resistance. Moreover, they can acquire high‐quality biopotential signals even after water rinsing and ultrasonic cleaning. These outstanding advantages enable the Kirigami‐structured PEDOT:PSS/PVA/Ag NWs/PU electrodes to effectively monitor human motions in real‐time and record epidermal biopotential signals, such as electrocardiogram, electromyogram, and electrooculogram under various conditions, and control external electronics, thereby facilitating human–machine interactions.

Self-Adhesive, Self-Healing, and Water-Soluble Polymeric Dry Electrodes for Robust Physiological Signal Monitoring

“…41 Furthermore, Xia et al demonstrated kirigamistructured epidermal electrodes composed of PEDOT:PSS/ polyvinyl alcohol(PVA)/Ag NWs/polyurethane, featuring high stretchability, low interfacial impedance, and skin conformity. 42 Although these electrodes can conform well to human skin under various deformations and are utilized as stretchable epidermal electrodes, the absence of self-healing capabilities may render the electrodes susceptible to damage during utilization, particularly when subjected to stressful conditions such as severe compression, torsion, or stretching. Such conditions can significantly compromise the longevity of the electrode, thereby limiting its overall performance and durability.…”