fig3

Figure 3. EIS spectra of (A) ZnO, (B) Mg-ZnO and (C) ZnO/Mg-ZnO. (D) Ionic conductivity of ZnO, Mg-ZnO and ZnO/Mg-ZnO at 420–520 °C. (E) Full XPS spectra and O 1s spectra of (F) ZnO, (G) Mg-ZnO and (H) ZnO/Mg-ZnO.