We report the synthesis of bimetallic Cu-Au nanotubes (NTs) and Cu@Au core-shell nanowires (NWs) for use as anti-oxidative electrodes. The fabrication involved two key approaches: galvanic replacement to produce Cu-Au NTs and the physical deposition of Au to form Cu@Au core-shell NWs. The galvanic replacement process generated hollow NTs through the Kirkendall effect, driven by the unequal diffusion rates of Cu and Au during the redox reaction. In contrast, the physical deposition of Au, facilitated by fast reduction kinetics using L-ascorbic acid, enabled the formation of a Au shell encapsulating the Cu NWs, preserving their structural integrity. Morphological and structural analyses confirmed the successful formation of both nanostructures. While the Cu-Au NTs exhibited hollow interiors and increased dimensions, the Cu@Au NWs displayed a solid core-shell morphology with minimal diameter increase. Electrical conductivity and thermal stability tests revealed the superior performance of the Cu@Au NWs. The sheet resistance of Cu@Au NWs remained as low as 4 Ω sq-1 and showed exceptional thermal stability, with minimal resistance variation (R/Ro ~1.36) even after 36 h at 120 °C under ambient conditions. In contrast, the Cu-Au NTs suffered rapid oxidation and structural instability. The physical deposition approach holds significant promise for the development of robust, low-resistance electrodes for long-term applications in harsh environments.

Abstract
1. Introduction
2. Experimental Procedure
    2.1. Materials
    2.2. Synthesis of Cu NWs
    2.3. Synthesis of bimetallic Cu-Au nanostructures
    2.4. Characterization
3. Results and Discussion
    3.1. Characterization of bimetallic Cu-Au NTs andCu@Au NWs
    3.2. Electrical conductivity and thermal stability
4. Conclusion
Acknowledgement
References
Author Information

• Seokhwan Kim(Department of Materials Science and Metallurgical Engineering, Kyungpook National University, Daegu 41566, Republic of Korea, Innovative Semiconductor Education and Research Center for Future Mobility, Kyungpook National University, Daegu 41566, Republic of Korea, Research Institute of Automotive Parts and Materials, Kyungpook National University, Daegu 41566, Republic of Korea)
• Geumseong Lee(Department of Materials Science and Metallurgical Engineering, Kyungpook National University, Daegu 41566, Republic of Korea, Innovative Semiconductor Education and Research Center for Future Mobility, Kyungpook National University, Daegu 41566, Republic of Korea, Research Institute of Automotive Parts and Materials, Kyungpook National University, Daegu 41566, Republic of Korea)
• Chanyeong Lee(Department of Materials Science and Metallurgical Engineering, Kyungpook National University, Daegu 41566, Republic of Korea, Innovative Semiconductor Education and Research Center for Future Mobility, Kyungpook National University, Daegu 41566, Republic of Korea, Research Institute of Automotive Parts and Materials, Kyungpook National University, Daegu 41566, Republic of Korea)
• Gyeongbok Yang(Department of Materials Science and Metallurgical Engineering, Kyungpook National University, Daegu 41566, Republic of Korea, Innovative Semiconductor Education and Research Center for Future Mobility, Kyungpook National University, Daegu 41566, Republic of Korea, Research Institute of Automotive Parts and Materials, Kyungpook National University, Daegu 41566, Republic of Korea)
• Yuho Min(Department of Materials Science and Metallurgical Engineering, Kyungpook National University, Daegu 41566, Republic of Korea, Innovative Semiconductor Education and Research Center for Future Mobility, Kyungpook National University, Daegu 41566, Republic of Korea, Research Institute of Automotive Parts and Materials, Kyungpook National University, Daegu 41566, Republic of Korea) Corresponding author
• Seonhwa Park(Regional Leading Research Center for Smart Energy System, Kyungpook National University, Daegu 41566, Republic of Korea)