Solid oxide fuel cell gadolinium-doped ceria

For a higher conductivity, cerium dioxide can be doped either with gadolinium Cei cGd (02 or with samarium Cex jSmj02 doped cerias are quite stable chemicdly. In solid oxide fuel cells they lack the effect of interactions between the electrolyte and the cathode materials that would lead to the formation of poorly conducting compounds. However, doped cerias have an important defect in that at low oxygen partial pressures (such as those existing close to the anode) they develop a marked electronic conduction. This is entirely inadmissible for the electrolyte, as it leads to internal self-discharge currents and even to a complete internal short circuit. The electronic conduction comes about when Ce" ions in the lattice are partly reduced to Ce " ions, which creates the possibility for electrons to hop between ions of different valency. 

Oishi N, Atkinson A, Brandon NP, Kilner JA, Steele BCH (2005) Fabrication of an anode-supported gadolinium-doped ceria solid oxide fuel cell and its operation at 550°C. J Am Ceram Soc 88(6) 1394-1396... 

Mermelstein J, MiUan M, Brandon NP (2011) The interaction of biomass gasification syngas components with tar in a solid oxide fuel cell and operational conditions to mitigate carbon deposition on nickel-gadolinium doped ceria anodes. J Power Sources 196 5027-5034... 

Atkinson, A. (1997) Chemically-induced stresses in gadolinium doped ceria solid oxide fuel cell electrolytes. Solid State Ionics, 95, 249-258. 

The materials that have been studied the most are yttria stabilized zirconia, doped ceria with gadolinium and lanthanum gallate doped with strontium and magnesium. The solid oxide fuel cells can, in principle, operate in a wide temperature range between 500 °C and... 

Y.M. Kim, P. Kim-Lohsoontorn et al.. Effect of unsintered gadolinium-doped ceria buffer layer on performance of metal-supported solid oxide fuel cells using unsintered barium strontium cobalt ferrite cathode. J. Power Sources 195(19), 6420-6427 (2010)... 

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