Enhanced stretchability of silver nanowire conductors based on pressure-induced double-layer conductive network for wearable electronics

Stretchable silver nanowire (AgNW) conductor are important components for stretchable electronics, but they face challenges of maintaining large stretchability, high conductivity, and mechanical robustness simultaneously. Here, a pressure-induced double-layer conductive network (PDLCN) is proposed to enhance the performance of AgNW conductors. The PDLCN is composed of a pressure-treated AgNW layer and an untreated AgNW layer. Compared with the untreated layer, the pressure-treated layer has a more compact internal structure. Under strain, AgNWs in each layer break at different positions and conductive bridges form between the two layers. As a result, the resistance increase ratio was reduced from 418 for the single-layer conductive network (SLCN) to 107 for the PDLCN at a strain of 100%. After 5000 cycles of stretching between 0% and 30% strain, the resistance increase ratio of the stretchable conductor with the PDLCN is ten times smaller than that of the SLCN conductor. The highly stretchable and stable conductors have been used to fabricate strain sensors and stretchable heaters, showing great potential for wearable electronics.