Ni-yttria-stabilized zirconia

Primdahl S and Mogensen M. Oxidation of hydrogen on Ni/yttria-stabilized zirconia cermet anodes. J Electrochem Soc 1997 144 3409-3419. 

Ihara, M., Kusano, T., Yokoyama, C. Competitive adsorption reaction mechanism of Ni/yttria-stabilized zirconia cermet anodes in H-2-H2O solid oxide fuel cells. J. Electrochem. Soc. 2001,148, A209-19. 

Hauch A, Ebbesen SD, Jensen SH, Mogensen M (2008) Solid oxide electrolysis cells microstructure and degradation of the Ni/yttria-stabilized zirconia electrode. JElectrochem Soc 155(11) B1184—B1193... 

Guzman, F., Singh, R., Chuang, S.S.C. (2011) Direct use of sulfur-containing coke on a Ni—Yttria-stabilized Zirconia anode solid oxide fuel cell. Energy Fuels, 25 (5), 2179-2186. 

Klemens, T., Thyden, K., Chen, M. Wang, H.J. Stability of Ni-yttria stabilized zirconia anodes based on Ni-impregnation.Power Sources 195 (2010), pp. 7295-7301. 

Brown M, Primdahl S, Mogensen M (2000) Structure/performance relations for Ni/yttria-stabilized zirconia anodes for solid oxide fuel cells. J Electrochem Soc 147 475 85... 

Diara, M., Yokoyama, C., Abudula, A., Kato, R., Komiyama, H., Yamada, K. (1999) Effect of the steam-methane ratio on reactions occurring on Ni/Yttria-stabilized Zirconia cermet anodes used in soUd-oxide fuel cells. Journal of the Electrochemical Society, 146, 2481-2487. 

D. Kek, M. Mogensen, and S. Pejovnik, A Study of Metal (Ni, Pt, Au)/Yttria-Stabilized Zirconia Interface in Hydrogen Atmosphere at Elevated Temperature, J. Electrochem. Soc. 148(8), A878-A886 (2001). 

There are a number of informative reviews on anodes for SOFCs [1-5], providing details on processing, fabrication, characterization, and electrochemical behavior of anode materials, especially the nickel-yttria stabilized zirconia (Ni-YSZ) cermet anodes. There are also several reviews dedicated to specific topics such as oxide anode materials [6], carbon-tolerant anode materials [7-9], sulfur-tolerant anode materials [10], and the redox cycling behavior of Ni-YSZ cermet anodes [11], In this chapter, we do not attempt to offer a comprehensive survey of the literature on SOFC anode research instead, we focus primarily on some critical issues in the preparation and testing of SOFC anodes, including the processing-property relationships that are well accepted in the SOFC community as well as some apparently contradictory observations reported in the literature. We will also briefly review some recent advancement in the development of alternative anode materials for improved tolerance to sulfur poisoning and carbon deposition. 

Currently, the standard SOFCs use yttria-stabilized zirconia (YSZ) (see Section 2.4.3) containing typically 8 mol% of Y02 as the electrolyte, a ceramic metal (a cermet) composed of Ni plus YSZ as the anode, and lanthanum strontium manganite (LSM) perovskite (La Sr, MnO,, ) as the cathode material [5,7,9,135],... 

The electrochemical reactions occurring within a SOFC are shown in Equations 25 and 26. The anode consists of a porous mixture of a Ni or Co catalyst on yttria-stabilized zirconia. Such a mixture of metal and ceramic is referred to as a cermet. The zirconia acts to inhibit grain growth of the catalyst particles of nickel or cobalt and protects against thermal expansion. The cathode is generally a Sr-doped... 

The heart of this system is an yttria-stabilized zirconia, Zr(Y)0 film, which acts as a solid electrolyte, allowing high conductivity for 0 ions at about 1,000°C. The fuel electrode is a porous Ni/ZrO cermet, which serves both as the electrocatalyst and as the current collector. Actually, electrocalalysis is no longer a problem at such elevated temperatures, and different fuels, including H, regular fossil fuels, and even CO, can be used. The air (oxygen) electrode is a... 

Another Ni-based solid oxide fuel cell (SOFC) electrode was developed on which a YSZ (yttria-stabilized zirconia) cermet and Lanthanum chromite were deposited by a slurry coating method. It was also suggested that a plasma spraying process can be used for the cermet deposition on the electrodes. The following reactions are expected to take place in a fuel cell employing a natural gas source, where internal reforming takes place on the Ni-YSZ electrode ... 

High ethylene selectivities (56-71%) were obtained using Ni, Mn, and Ti oxides promoted with LiCl. At 750 °C and P = 0.05 atm, Ti+LiCl gave 83% Cj+ selectivity at 18% conversion. Oxygen was electrochemically pumped through yttria-stabilized zirconia as a... 

G. O. Lauvstad, R. Tunold, and S. Sunde. Electrochemical oxidation of CO on Pt and Ni point electrodes in contact with an yttria- stabilized zirconia electrolyte. J. Electrochem. Soc. 149, (2002) E497-E505. 

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