辅助物体追踪的4D-STEM断层成像框架用于纳米颗粒结构解析
A 4D-STEM Tomographic Framework Assisted by Object Tracking for Nanoparticle Structure Determination
AI总结：
本研究提出结合4D-STEM断层成像与物体追踪算法的方法，用于解析纳米颗粒结构，克服了传统3D ED在敏感样品和团聚颗粒中的技术限制。
摘要：
三维电子衍射（3D ED）已发展为一种强大的方法，用于解析亚微米级颗粒结构，甚至纳米颗粒结构。然而，当应用于对束敏感样品或聚集和团聚纳米颗粒时，会面临技术挑战。本研究提出了一种新的方法，结合4D-STEM断层成像与物体追踪和分割算法，以克服这些限制，并从纳米粉末样品中获得单晶3D ED数据集。该方法和数据质量在brookite TiO2纳米棒和对束敏感的CsPbBr3纳米颗粒上进行了评估。为了精细采样倒易空间，数据采集被自动化，使用略微会聚的束和细小的倾斜步骤，以获取数百个4D-STEM扫描。所提出的方法提供了更高的信噪比，较低的照明时间以减少束损伤，并能够从单个断层数据集中分析多个颗粒。该过程被优化，以便使用商用台式机和探测器实现。这将该方法的应用范围扩展到传统3D ED方法以前无法触及的系统和样品，特别是突破了传统3D ED方法的数据采集技术挑战。
英文摘要：
Three-dimensional electron diffraction (3D ED) has emerged as a powerful method for solving the structures of sub-micron-sized particles down to nanoparticles. However, it faces technical challenges when applied to beam-sensitive samples or agglomerated nanoparticles. This study presents a novel approach that combines 4D-STEM tomography with object tracking and segmentation algorithms to overcome these limitations and achieve single-crystalline 3D ED datasets from nanopowder samples. The method and data quality are assessed on brookite TiO2 nanorods and beam-sensitive CsPbBr3 nanoparticles. To finely sample the reciprocal-space, the data acquisition was automated to acquire hundreds of 4D-STEM scans at fine tilt steps using a slightly convergent beam (0.6 to 1 mrad). Compared to conventional 3D ED methodologies, the proposed method provides enhanced signal-to-noise ratio, low illumination time for reducing beam damage, and the ability to analyze multiple particles from a single tomographic dataset. The procedure is optimized to be feasible using commercially available desktops and detectors. This extends the method applicability to systems and samples that were very challenging for conventional 3D ED methods, by eliminating several technical challenges for the data acquisition.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
