fig9

Figure 9. (A) Fit of the powder X-ray diffraction pattern of the sample obtained by the thermal decomposition of Li_1.5Mn_1.5O_3.5 at 600 °C with a mixture of Li₂MnO₃ and LiMn₂O₄ phases; (B) HAADF-STEM images of the nanocrystalline phases in the sample obtained by the thermal decomposition of Li_1.5Mn_1.5O_3.5 at 600 °C; (C) Ring electron diffraction patterns of the small (left) and large crystals (right) in phase (B); (D) Intensity profiles of the ring ED patterns indexed with the spinel F-centered cubic cell (top) and the Li₂MnO₃C-centered monoclinic unit cell (bottom); (E) Theoretical electron diffraction pattern of the Li₂MnO₃ phase (top) and the theoretical electron diffraction pattern of the Li₂MnO₃ phase affected by preferred orientation; (F) HAADF-STEM image, Mn and O EDX signal maps and a mixed colored map; (G) EDX spectra at the O-K_α and Mn-L_α lines indicating that the large Li₂MnO₃ crystal (area 2 in the panel F) has a higher O-content (red spectrum). The spectrum of the area of small LiMn₂O₄ crystals (area 1, blue spectrum) demonstrates a clearly lower intensity of the O-K line compared to that of the large Li₂MnO₃ crystals (red); (H) ED patterns of the Li₂MnO₃ phase. The reflections due to spinel intergrowth are marked with arrows. HAADF-STEM: High angle annular dark field scanning transmission electron microscopy; ED: Electron diffraction; EDX: Energy dispersive X-ray.