Ceria doped with trivalent cations

Gerhardt, R., and Nowick, A. S. (1986). Grain-boundary effect in ceria doped with trivalent cations I. Electrical measurements./. Am. Ceram. Soc. 69 641-646. 

Steele and Floyd were the first to show that solid solutions of ceria with rare earth oxides promote the reduction of Ce at temperatures below 900 °C. Since then, a large number of investigations on ceria doped with lower valent cations have verified this observation.The value of AHq at v 0 has been found to decrease (in absolute value) for increasing doping at least up to 20 mol% of trivalent and 14 mol% of divalent doping. 

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