Ultralong Silver Nanowires Patterning Using Intaglio Printing for High-Resolution Wearable Electrophysiological Sensors

Abstract

Silver nanowires (NWs), with their superior electrical, thermal, and mechanical properties, are ideal for flexible electronics such as electronic skins. Achieving precise patterning of Ag NWs is crucial for integrating and miniaturizing electronic devices. However, their high aspect ratio (AR) and network porosity pose challenges for high-resolution patterns. We present an intaglio transfer printing technique for ultralong Ag NWs (AR≈1000). During pattern formation, external force concentrates at the intaglio trench edge, breaking the NW network. This technique allows precise, high-resolution (minimum line width: 7 μm) patterns on flexible substrates. Patterned Ag NWs attach conformally to curvilinear surfaces and remain stable under bending. Wearable sensors using these patterns monitor electromyography and electrocardiogram signals in real-time, showcasing their potential in wearable electronics. This strategy highlights an effective approach for high-resolution patterns of anisotropic nanomaterials.