Surface character and oxygen migration

FIGURE 30 The activity of the Tb atoms on the surface of 111 facets of TbO. The four arrows indicate the nano-twin crystal. The atoms at the right upper corner are very active during the electron beam radiation. Its temperature is about 600 °C. The left surface of this nano-twin is the 111 surface which has a low energy, and atoms at this surface are not active. 

FIGURE 31 The oxygen migration and the valence variation of the Ce cations. 

FIGURE 32 The homologous phase of the CeC 2s electrolyte between the cathode and anode as the oxygen partial pressure decreases from the cathode to the anode. 

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