Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia.
Materials Engineering and Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, QLD, 4072, Australia.
Adv Mater. 2019 Sep;31(38):e1801564. doi: 10.1002/adma.201801564. Epub 2018 Aug 30.
Innovations in nanofabrication have expedited advances in hollow-structured nanomaterials with increasing complexity, which, at the same time, set challenges for the precise determination of their intriguing and complicated 3D configurations. Conventional transmission electron microscopy (TEM) analysis typically yields 2D projections of 3D objects, which in some cases is insufficient to reflect the genuine architectures of these 3D nano-objects, providing misleading information. Advanced analytical approaches such as focused ion beam (FIB) and ultramicrotomy enable the real slicing of nanomaterials, realizing the direct observation of inner structures but with limited spatial discrimination. Electron tomography (ET) is a technique that retrieves spatial information from a series of 2D electron projections at different tilt angles. As a unique and powerful tool kit, this technique has experienced great advances in its application in materials science, resolving the intricate 3D nanostructures. Here, the exceptional capability of the ET technique in the structural, chemical, and quantitative analysis of hollow-structured nanomaterials is discussed in detail. The distinct information derived from ET analysis is highlighted and compared with conventional analysis methods. Along with the advances in microscopy technologies, the state-of-the-art ET technique offers great opportunities and promise in the development of hollow nanomaterials.
纳米制造的创新加速了具有日益复杂结构的中空纳米材料的发展，但同时也对精确确定其引人入胜且复杂的 3D 结构提出了挑战。传统的透射电子显微镜（TEM）分析通常只能获得 3D 物体的 2D 投影，在某些情况下，这不足以反映这些 3D 纳米物体的真实结构，从而提供误导性信息。先进的分析方法，如聚焦离子束（FIB）和超微切割，能够对纳米材料进行真正的切片，实现对内部结构的直接观察，但空间分辨率有限。电子断层扫描（ET）是一种从不同倾斜角度的一系列 2D 电子投影中获取空间信息的技术。作为一种独特而强大的工具包，该技术在材料科学中的应用取得了重大进展，解决了复杂的 3D 纳米结构问题。本文详细讨论了 ET 技术在中空纳米材料的结构、化学和定量分析中的特殊能力。突出了 ET 分析得出的独特信息，并与传统分析方法进行了比较。随着显微镜技术的进步，最先进的 ET 技术为中空纳米材料的发展提供了巨大的机会和前景。
