Gadolinium doped ceria

Ni-cermet type anodes have been improved by substituting the YSZ by ceria, gadolinium-doped ceria (GDC) and samarium-doped ceria (SDC). Ceria seems to increase the catalytic activity of the cermet for hydrogen oxidation, while SDC and GDC improve the ionic conductivity of the anode. Ni-ceria cermets are considered the main candidate for low-temperature SOFC [74],... 

Metallic gold has also been dissolved from pure ceria,51 from gadolinium-doped ceria,51 and from catalysts made by a urea gelation/coprecipitation method ,52 without significant effect on their activities for water-gas shift. The only problem that has been identified is the formation of a cerium hydroxycarbonate, which occurs during shut-down when water is present. The very extensive work performed on this system48-52 ensures that its conclusions are given full consideration. 

Demonstrated the performance of Rh-, Ni-, and Pt-CGO (gadolinium-doped ceria) supported on a... 

Gadolinium-doped ceria (CGO) substrates are prepared from nitrate salt precursors by either coprecipitation or glycine-nitrate combustion techniques. Pt, Rh, orNi is loaded onto the CGO using the incipient wetness technique. Typical weight loadings are 1 wt% or less for Pt and Rh and up to 10... 

AFC Alkaline Fuel Cell CGO Gadolinium-Doped Ceria... 

S. Llibke, H.-D. Wiemhofer, Electronic Conductivity of Gadolinium Doped Ceria, Ber. Bunsenges. Phys. Chem., 102, 642 (1998). 

Silicate apatite conductivity compared to that of YSZ, GDC (gadolinium-doped ceria) and LSGM (lanthanum- and strontium-doped magnesium gallate) (Marero-Lopez etai, 2010). 

Avila-Paredes HJ, Kim S (2006) The effect of segregated transition metal ions on the grain boundary resistivity of gadolinium doped ceria alteration of the space charge potential. Solid State Ion 177 3075-3080... 

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... 

Maher RC, Cohen LF (2008) Raman spectroscopy as a prohe of hanptuatnre and oxidation state for gadolinium-doped ceria used in soUd oxide fuel cells. J Phys Chem A 112(7) 1497-1501... 

Ball and Stevens (74) report that gadolinium-doped ceria is a good candidate for use as an alternative electrolyte when compared to zirconia, due to its higher conductivity at lower temperatures. However, doped ceria has a number of disadvantages, such as electronic conductivity and reduced strength. Results indicate that an increase in strength can be produced in the ceria by addition of zirconia particles that is dependent on the particle size and heat treatment. 

Sheldon W. Brian, Nicholas D. Jason, and Mandowara Sunil. Tensile stress evolution during the early-stage constrained sintering of gadolinium-doped ceria films. J. Am. Ceram. Soc. 94 no. 1 (2011) 110-117. 

Typical electrolyte materials for SOFCs are oxides with low valence element substitutions, sometimes named acceptor dopants [13, 95] which create oxygen vacancies through charge compensation. For SOFC applications, there are various materials that have been explored as electrolyte, yttria-doped zirconia (YSZ) and gadolinium-doped ceria (GDC) are the most common materials used for the oxideconducting electrolyte. Above 800 °C, YSZ becomes a conductor of oxygen ions (02-) zirconia-based SOFC operates between 800 and 1100 °C. The ionic conductivity of YSZ is 0.02 S m at 800 °C and 0.1 S cm at 1000 °C. A thin electrolyte (25-50 (im) ensures that the contribution of electrolyte to the ohmic loss in the SOFC is kept to a minimum. 

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. 

CGO gadolinium-doped ceria (Cei jcGdjc02) cso samarium-doped ceria (Cei-jcSmjc02)... 

Figure 8.11 SEM photographs of gadolinium-doped ceria powders derived using different amounts of polyvinylpyrrolidone surfactant (a) SI (2 x 10" g-ml ). (b) S2 (4 X 10 g.ml ). (c) S3 (8 x KT g.ml ). (d) S4 (1.2 x 10 g.ml ). Reprinted from Youkun et alP with permission from Elsevier.

Fuentes, R.O. and Baker, R.T. (2008) Synthesis and properties of gadolinium-doped ceria solid solutions for IT-SOFC electrolytes. Int. J Hydrogen Energy,... 

Figure 15. (a) Cross-sectional view of SSC (Samarium Strontium Cobalt Oxide) GDC (Gadolinium-doped Ceria) copper foam, (b) and (c) are the magnified images of SSC I GDC and GDC copper foam, respectively. 

P. P. Dholabhai, S. Anwar, J. B. Adams, P. A. Crozier, and R. Sharma, Model. Simul. Mater. Sci., 20, 13 (2012). Predicting the Optimal Dopant Concentration in Gadolinium Doped Ceria A Kinetic Lattice Monte Carlo Approach. 

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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