School of Materials Science and Engineering, Hefei University of Technology, Hefei, Anhui Province, 230009, China.
Department of Materials Science and Engineering, University of California at Berkeley & The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
Small. 2022 Oct;18(41):e2203310. doi: 10.1002/smll.202203310. Epub 2022 Sep 9.
The rapid advancement of transmission electron microscopy has resulted in revolutions in a variety of fields, including physics, chemistry, and materials science. With single-atom resolution, 3D information of each atom in nanoparticles is revealed, while 4D electron tomography is shown to capture the atomic structural kinetics in metal nanoparticles after phase transformation. Quantitative measurements of physical and chemical properties such as chemical coordination, defects, dislocation, and local strain have been made. However, due to the incompatibility of high dose rate with other ultrathin morphologies, such as nanowires, atomic electron tomography has been primarily limited to quasi-spherical nanoparticles. Herein, the 3D atomic structure of a complex core-shell nanowire composed of an ultrathin Boerdijk-Coxeter-Bernal (BCB) core nanowire and a noble metal thin layer shell deposited on the BCB nanowire surface is discovered. Furthermore, it is demonstrated that a new superthin noble metal layer deposition on an ultrathin BCB nanowire could mitigate electron beam damage using an in situ transmission electron microscope and atomic resolution electron tomography. The colloidal coating method developed for electron tomography can be broadly applied to protect the ultrathin nanomaterials from electron beam damage, benefiting both the advanced material characterizations and enabling fundamental in situ mechanistic studies.
透射电子显微镜的快速发展在物理、化学和材料科学等多个领域引发了革命。具有单原子分辨率，可以揭示纳米粒子中每个原子的 3D 信息，而 4D 电子断层扫描则可以捕获金属纳米粒子相变后原子结构动力学。已经对化学配位、缺陷、位错和局部应变等物理和化学性质进行了定量测量。然而，由于高剂量率与其他超微形态（如纳米线）不兼容，原子电子断层扫描主要局限于准球形纳米粒子。在此，发现了由超薄 Boerdijk-Coxeter-Bernal (BCB) 核纳米线和沉积在 BCB 纳米线表面的贵金属薄壳组成的复杂核壳纳米线的 3D 原子结构。此外，还证明了在原位透射电子显微镜和原子分辨率电子断层扫描中，在超薄 BCB 纳米线上新沉积一层超薄贵金属层可以减轻电子束损伤。为电子断层扫描开发的胶体涂层方法可以广泛应用于保护超薄纳米材料免受电子束损伤，既有利于先进材料特性的研究，也有利于基础的原位力学研究。
