This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.
 

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Figure 3423a (a) shows a TEM image of a RuO₂/TiO₂ core/shell structure (a RuO₂ nanorod shelled with a TiO₂ layer) in diameter of 160 nm. Figure 3423a (b) shows the EELS spectra taken from the selected positions in Figure 3423a (a) that are marked by A and B for the RuO₂/TiO₂ core/shell structure and a pure RuO₂ nanorod without TiO₂ coating, respectively. For the EEL spectrum from the TiO₂ shell (position B), the ELNESs of Ti L_2,3- and O K-edges are clearly found. In the spectrum obtained from position A, the Ru M-edge is present, while the Ti L_2,3- and O K-edges are not so clear because the wire-shaped specimen is too thick (about 220 nm in wire-diameter) for EELS measurements.

Figure 3423a. (a). The TEM image of a RuO₂/TiO₂ core/shell structure in diameter of 160 nm. (b) EELS spectrum for the Ti L-edge and O K-edge ELNEFS of the RuO₂/TiO₂ core/shell structure taken from two points, labeled A and B for the RuO₂/TiO₂ wire and the TiO₂ shell, respectively. The bottom EELS spectrum was obtained from a pure RuO₂ nanorod as reference. Adapted from [2]

The EEL spectra in Figure 3423b presents Ru M_4,5 edges in a series of Co–Ru_x–B-O catalysts. By comparison with the references (commercial RuO₂ powder and pure Ru foil), ruthenium in Co–Ru_x–B-O catalysts seems to be highly reduced all around the series with 0.13≤ x_Ru ≤ 1.

Figure 3423b. Ru M_4,5 edges in the EELS spectra of Co–Ru–B-O catalysts. [3]

Pearson et al. [1] experimentally and theoretically (based on one-electron Hartree-Slater calculations) found that the intensities of L_2,3 white lines for most of the 3d and 4d transition metals decreased nearly linearly with increasing atomic number, reflecting the filling of the d states. Figure 3423c shows the deconvoluted and background-subtracted L_2,3 energy-loss spectra for the 4d transition metals. The edge energies are not shown in order to present all the spectra on the same figure, while the intensities of the white lines are scaled simultaneously for all elements.

Figure 3423c. The deconvoluted and background-subtracted L_2,3 energy-loss spectra for the 4d transition metals. [1]

[1] D. H. Pearson, C. C. Ahn, and B.Fultz, White lines and d-electron occupancies for the 3d and 4d transition metals, Physical Review B, 47(14), (1993) 8471-8478.
[2] Yu-Lun Chueh, Chin-Hua Hsieh, Mu-Tung Chang, Li-Jen Chou, Chang S. Lao, Jin H. Song, Jon-Yiew Gan, and Zhong L. Wang, RuO₂ Nanowires and RuO₂/TiO₂ Core/Shell Nanowires: From Synthesis to Mechanical, Optical, Electrical, and Photoconductive Properties, Advanced Materials, 2007, 19 (1), 143–149.
[3] G.M. Arzac, T.C. Rojas, A. Fernández, New insights into the synergistic effect in bimetallic-boron catalysts for hydrogen generation: The Co–Ru–B system as a case study, Applied Catalysis B: Environmental 128 (2012) 39– 47.