Rational design of robust Cu@Ag core-shell nanowires for wearable electronics applications

Copper nanowires (CuNWs) have shown great potential as transparent electrodes for cost-effective wearable electronics. However, its unsatisfactory electrical conductivity and intrinsic susceptibility to oxidation hinder practical applications. To address these issues, herein, ultra-stable Cu@Ag core-shell NWs have been designed via a facile galvanic replacement method for wearable applications. The thermal stability of the NWs is significantly enhanced after introducing Ag, and superior stability is achieved with a more uniform Ag coating. The structural integrity of the percolation networks is basically maintained after 5 days' annealing treatment at a high temperature (>= 150 degrees C). The devices based on core-shell NWs show reliable heating performance, and can further be used for defrosting and heating water/ice applications. Owing to optimized contact between Ag-coated NWs, the devices exhibit excellent mechanical performance under repetitive bending. Based on above structural design, the resultant strain sensors show high sensitivity, good repeatability and a wide sensing range, which are capable to detect various hand gestures and communicate with Morse code. Furthermore, the fabricated core-shell NWs show robust antibacterial activity, which is essential for wearable healthcare applications, outperforming that of pristine CuNWs. This work provides a promising way for the design of high-performance metal NWs for advanced wearable electronics.