Ultrathin Gold Nanowires.

Abstract

Nanowires (NWs), particularly Au NWs, have garnered significant attention for their exceptional properties and applications as nanoscale interconnects in micro-nano electronics. Nevertheless, the stable structure of sub-2nm Au NWs continues to be ambiguous due to the significant challenges in both the fabrication processes and direct atomic-scale structural characterization. This study employs in situ transmission electron microscopy (TEM) techniques combined with the Perdew-Burke-Ernzerhof (PBE) functional within density functional theory (DFT) to systematically investigate the intrinsic relationship between the atomic structure and stability of oriented Au NWs. Our results indicate that the structural stability of Au NWs is influenced by both their structural symmetry and the proportion of (111) surfaces. Additionally, the Young's modulus of Au NWs is related to their cross-sectional symmetry, with an inverse correlation observed when the equivalent radius is below 6 Å. Finally, the number of conductive channels in Au NWs increases with cross-sectional size, with higher symmetry exhibiting more conducting channels. The experimental results offer significant insights into the key determinants influencing the structural integrity of ultrathin gold nanowires, which serves as a crucial basis for their implementation in next-generation nanoscale device technologies.