Nickel-zirconia cermet

Kawada T, Sakai N, Yokokawa H, Dokiya M, Mori M, and Iwata T. Characteristics of slurry-coated nickel zirconia cermet anodes for solid oxide fuel cells. J Electrochem Soc 1990 137 3042-3047. 

The stack electrolytes are scandia-stabilised zirconia, about 140 (im thick. The air-side electrodes (anode in the electrolysis mode) are a strontium-doped manganite. The electrodes are graded, with an inner layer of manganite/zirconia ( 13 pm) immediately adjacent to the electrolyte, a middle layer of pure manganite ( 18 pm), and an outer bond layer of cobaltite. The steam/hydrogen electrodes (cathode in the electrolysis mode) are also graded, with a nickel-zirconia cermet layer ( 13 pm) immediately adjacent to the electrolyte and a pure nickel outer layer ( 10 pm). 

The basic elements of a SOFC are (1) a cathode, typically a rare earth transition metal perovskite oxide, where oxygen from air is reduced to oxide ions, which then migrate through a solid electrolyte (2) into the anode, (3) where they combine electrochemically with to produce water if hydrogen is the fuel or water and carbon dioxide if methane is used. Carbon monoxide may also be used as a fuel. The solid electrolyte is typically a yttrium or calcium stabilized zirconia fast oxide ion conductor. However, in order to achieve acceptable anion mobility, the cell must be operated at about 1000 °C. This requirement is the main drawback to SOFCs. The standard anode is a Nickel-Zirconia cermet. 

P. Holtappels, I. C. Vinke, E. G. J. de Haart, and U. Stimming. Reaction of hydro-gen/water mixtures on nickel-zirconia cermet electrodes II AC polarization characteristics. /. Electrochem. Soc. 146, (1999) 2976-2982. 

M. Cassidy, Q. Lindsay and K. Kendall, The reduction of nickel-zirconia cermet anodes and the effects on supported thin electrolytes, J. Power Sources, 61, p. 189 (1996)... 

Holtappels P, Vinke IC, de Haart LGJ, Slimming U (1999) Reaction of hydrogen/water mixtures on nickel-zirconia cermet electrodes. 2. AC polarization characteristics. J Electrochem Soc 146 2976-2982... 

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