Cu@Ag core-shell NWs for printed electronics: synthesis, stability, and device integration

Printed electronics is an emerging technology that has already transformed the world around us by enabling the fabrication of flexible, lightweight, and large-area electronic devices. However, achieving simultaneous optimization of electrical conductivity, environmental stability, mechanical flexibility, and cost efficiency remains a critical challenge. Nanowires (NWs) have gained prominence in various applications due to their high surface area to volume ratio. Silver NWs (Ag NWs) in particular have established themselves as leading platforms for transparent conductive electrodes (TCE), however their high cost and material consumption limit widespread adoption. While copper NWs (Cu NWs) offer cost advantages and comparable conductivity to silver; rapid oxidation and corresponding increase in resistivity in ambient conditions restrict their widespread adoption. Cu@Ag core-shell NWs (Cu@Ag NWs) are a promising solution, combining the cost efficiency of copper with the oxida0074ion resistance of silver through a strategic thin-shell design. This mini-review focuses on recent advances in Cu@Ag NWs synthesis, focusing particularly on kinetically controlled approaches that achieve conformal silver shells lowering the consumption of silver. We examine synthesis methodologies, including galvanic displacement and chemical reduction, discuss mechanisms underlying long-term environmental stability, and evaluate integration pathways for printed electronics applications including, transparent conductive films, flexible displays, wearable devices, and electromagnetic interference (EMI) shielding. Challenges and future considerations, including shell uniformity control, ink formulation optimization, and multi-functional coating systems incorporating protective oxide layers, are also addressed. This review provides a comprehensive framework for advancing Cu@Ag NWs technology toward practical commercial implementation in next-generation flexible and printed electronics.