Figure 3

(A) CFO-NOsmall elemental mapping performed on the same areas at different magnifications. On the left, TEM-ZLP bright field images show an overview of the sample; in the middle, Fe (blue), Co (green) and Ni (red) EFTEM mapping are overlapped; on the right, oxygen elemental mapping (yellow) highlights the O-poor zones, which correspond to metallic grains. (B) CFO-NOlarge elemental mapping performed on two different areas (top) and (bottom). On the left, TEM-ZLP images show an overview of the sample; in the middle, Fe (blue), Co (green) and Ni (red) mapping are overlapped; on the right, oxygen elemental mapping (yellow) highlights the O-poor zones, which correspond to metallic grains.