Fabrication of Metal Nanowire Based Stretchable Mesh Electrode for Wearable Heater Application

Abstract

In recent years, human-convenient smart wearable devices have attracted considerable attention as emerging applications in smart healthcare systems, soft robotics, and human-machine interfaces. In particular, resistive film heaters with mechanical flexibility and excellent mechanical and electrothermal performance have recently been widely explored for wearable thermotherapy applications. Here, we present a simple and efficient way of fabricating highly flexible and stretchable resistive film heaters based on a patterned silver nanowire (AgNW)/polymer composite structure. The AgNW/polymer composite electrodes were successfully prepared using a photolithographically patterned polymer mold based selective transfer of a AgNW percolation network. The photolithographic mold patterning process allows the heater fabrication to be precise and reproducible. The mesh-patterned AgNW/polymer composite heater exhibited the excellent electrothermal performance of ~46.7 oC at 3 V. This low-voltage operation is highly desirable in practical wearable device applications. Moreover, the AgNW/polymer heater can be stretched up to 20% without significant degradation in electrothermal performance thanks to its open-cell architecture, suggesting that the device can stably transfer heat to the skin after being attached to various body parts with curvilinear surfaces. The experimental results suggest that the mesh-structured AgNW/polymer composite heaters are highly feasible for use as a wearable thermotherapy tool in many emerging applications.