Alloying and Embedding of Cu-Core/Ag-Shell Nanowires for Ultrastable Stretchable and Transparent Electrodes

In this paper, transparent electrodes with dense Cu@Ag alloy nanowires embedded in the stretchable substrates are successfully fabricated by a high-intensity pulsed light (HIPL) technique within one step. The intense light energy not only induces rapid mutual dissolution between the Cu core and the Ag shell to form dense Cu@Ag alloy nanowires but also embeds the newly formed alloy nanowires into the stretchable substrates. The combination of alloy nanowires and embedded structures greatly improve the thermal stability of the transparent electrodes that maintain a high conductivity unchanged in both high temperature (140 °C) and high humidity (85 °C, 85% RH) for at least 500 h, which is much better than previous reports. The transparent electrodes also exhibit high electromechanical stability due to the strong adhesion between alloy nanowires and substrates, which remain stable after 1000 stretching-relaxation cycles at 30% strain. Stretchable and transparent heaters based on the alloyed and embedded electrodes have a wide outputting temperature range (up to 130 °C) and show excellent thermal stability and stretchability (up to 60% strain) due to the alloy nanowires and embedded structures. To sum up, this study proposes the combination of alloying and embedding structures to greatly improve the stability of Cu nanowire-based stretchable transparent electrodes, showing a huge application prospect in the field of stretchable and wearable electronics.