Laboratory of Electron Nanoscopies (LENS)-MIND/IN2UB, Dept. d'Electrònica, Universitat de Barcelona, c/ Martí Franquès 1, E-08028 Barcelona, Spain.
Ultramicroscopy. 2012 Nov;122:12-8. doi: 10.1016/j.ultramic.2012.07.020. Epub 2012 Jul 24.
Electron tomography is a widely spread technique for recovering the three dimensional (3D) shape of nanostructured materials. Using a spectroscopic signal to achieve a reconstruction adds a fourth chemical dimension to the 3D structure. Up to date, energy filtering of the images in the transmission electron microscope (EFTEM) is the usual spectroscopic method even if most of the information in the spectrum is lost. Unlike EFTEM tomography, the use of electron energy-loss spectroscopy (EELS) spectrum images (SI) for tomographic reconstruction retains all chemical information, and the possibilities of this new approach still remain to be fully exploited. In this article we prove the feasibility of EEL spectroscopic tomography at low voltages (80 kV) and short acquisition times from data acquired using an aberration corrected instrument and data treatment by Multivariate Analysis (MVA), applied to Fe(x)Co((3-x))O(4)@Co(3)O(4) mesoporous materials. This approach provides a new scope into materials; the recovery of full EELS signal in 3D.
电子断层扫描是一种广泛应用于恢复纳米结构材料三维（3D）形状的技术。使用光谱信号来实现重建为 3D 结构增加了第四个化学维度。迄今为止，即使在光谱中丢失了大部分信息，透射电子显微镜（EFTEM）中的图像能量过滤（EFTEM）仍然是常用的光谱方法。与 EFTEM 断层扫描不同，电子能量损失光谱（EELS）谱图像（SI）用于断层重建保留了所有化学信息，这种新方法的可能性仍有待充分利用。在本文中，我们证明了在低电压（80kV）下使用具有像差校正仪获取的数据和通过多变量分析（MVA）进行数据处理进行 EEL 光谱断层扫描的可行性，该方法适用于 Fe(x)Co((3-x))O(4)@Co(3)O(4)介孔材料。这种方法为材料提供了新的研究范围，可以在 3D 中恢复完整的 EELS 信号。
