Yang Dahai, Zhang Xingyu, Yang Ruijie, Zou Bolin, Huang Rui, Ophus Colin, Song Chengyu, Cheng Sheng, Kim Juyeong, Xiong Hui, Wu Xianqi, Li Mufan, Wang Yong, Xiang Hongfa, Ou Zihao, Song Xiaohui
School of Materials Science and Engineering, Hefei University of Technology, Hefei, Anhui Province, P.R. China.
School of Mathematics, Statistics and Mechanics, Beijing University of Technology, Beijing, P.R. China.
Nat Commun. 2025 May 23;16(1):4795. doi: 10.1038/s41467-025-60135-3.
The surface morphology and shape of crystalline nanowires significantly influence their functional properties, including phonon transport, electrocatalytic performance, to name but a few. However, the kinetic pathways driving these morphological changes remain underexplored due to challenges in real-space and real-time imaging at single-particle and atomic resolutions. This study investigates the dynamics of shell (Au, Pd, Pt, Fe, Cu, Ni) deposition on AuAg alloy seed nanowires during core-shell formation. By using chiral/non-chiral seed nanowires, advanced imaging techniques, including liquid-phase transmission electron microscopy (LPTEM), cryogenic TEM, and three-dimensional electron tomography, a three-step deposition process is revealed: heterogeneous nucleation, nanoparticle attachment, and coalescence. It is found that colloidal Ostwald ripening, metal reactivity, and deposition amount modulate nanoparticle size and surface roughness, shaping final morphologies. Noble metal nanoparticles (Au, Ag, Pd, Pt) coalesce with seed nanowire along the 〈111〉 direction, distinct from that of other metals. These findings are consistent across different metals, including Ru, Cu, Fe, and Ni, highlighting the hypothesis of these processes in nanowire formation. These findings enhance traditional crystallographic theories and provide a framework for designing nanowire morphology. Additionally, our imaging techniques may be applied to investigate phenomena like electrodeposition, dendrite growth in batteries, and membrane deformation.
晶体纳米线的表面形态和形状显著影响其功能特性，包括声子传输、电催化性能等等。然而，由于在单粒子和原子分辨率下进行实空间和实时成像存在挑战，驱动这些形态变化的动力学途径仍未得到充分探索。本研究调查了在核壳形成过程中，壳层（金、钯、铂、铁、铜、镍）在金银合金籽晶纳米线上的沉积动力学。通过使用手性/非手性籽晶纳米线、先进的成像技术，包括液相透射电子显微镜（LPTEM）、低温透射电子显微镜和三维电子断层扫描，揭示了一个三步沉积过程：异质成核、纳米颗粒附着和聚结。研究发现，胶体奥斯特瓦尔德熟化、金属反应性和沉积量会调节纳米颗粒的大小和表面粗糙度，从而塑造最终形态。贵金属纳米颗粒（金、银、钯、铂）沿〈111〉方向与籽晶纳米线聚结，这与其他金属不同。这些发现对于包括钌、铜、铁和镍在内的不同金属都是一致的，突出了这些过程在纳米线形成中的假设。这些发现完善了传统晶体学理论，并为设计纳米线形态提供了一个框架。此外，我们的成像技术可用于研究电沉积、电池中枝晶生长和膜变形等现象。
