fig2
Figure 2. SEM, TEM, HRTEM and HAADF images of (A, E, I and M) ZnCo2O4, (B, F, J and N) Zn1-xCo2NixO4, (C, G, K and O) ZnCo2-yFeyO4 and (D, H, L and P) Zn1-xCo2-yNixFeyO4. SEM: Scanning electron microscopy; TEM: transmission electron microscopy; HRTEM: high-resolution TEM; HAADF: high-angle annular dark field.
