Ceramic oxide anodes

Gorges et al. [155] introduced anodic spark deposition (ASD), a modification of anodic oxidation, for the formation of polycrystalline ceramic oxide layers on passivating metals (Figure 2.99). The method is therefore limited to Ti, Al and Zr... 

Figure 22 Bipolar cell for aluminum electrolysis due to Alusuisse [236], The vertical bipolar electrodes consist of 3, an anode layer, a ceramic oxide 4, an intermediate conducting layer 5, a cathode layer, e.g., TiB2. 

The electrostatic capacitor uses organic polymer, mica, glass, ceramic, and anodic oxide film... 

Fig. 1 Schematic of a SOFC consisting of a porous anode and cathode separated by a dense, impermeable ceramic oxide electrolyte. Figure reproduced from reference [4],...

Metal Supported-Solid Oxide Fuel Cells (MS-SOFC) represent a promising new design for fuel cells which may overcome the limitations of anode-supported cells (such as poor thermal cycling resistance and brittleness. Nickel phase re-oxidation upon exposure to transient uncontrolled conditions) due to the much better mechanical properties of the support that is represented by a porous thick metal substrate, the thickness of the ceramic layers (anode/electrolyte/cathode) being in the order of 10-50 pm, only. In addition, in this design (Fig. 1), the replacement of the thick Ni/YSZ cermet with ferritic stainless steel leads to several benefits in term of fabrication cost and safety. 

Liu J, Madsen BD, Ji ZQ, Barnett SA (2002) A fuel-flexible ceramic-based anode for solid oxide fuel cells. Electrochem Solid State Lett 5 A122-A124... 

Fu Q, Tietz F, Sebold D, Tao S, Irvine ITS (2007) An efficient ceramic-based anode for solid oxide fuel cells. J Power Sources 171 663-669... 

Fu, Q.X. Tietz, E Ceramic-based anode materials for improved redox cycling of solid oxide fuel-cells. Fuel-Cells 8 (2008), pp. 283-293. 

A US company has been developing a fuel cell based on a ceramic oxide electrolyte to operate at about 1000° C. It is able to consume either hydrogen or hydrogen-carbon monoxide mixtures (reformed natural gas, etc.) as the anode fuel. Unlike all the other systems which are based on stacks of parallel porous electrodes, the design here is centred on a ceramic oxide tube and cylindrical electrodes. A number of 3 kW units with 144 cells are under test to check performance and to ascertain lifetime under practical conditions. A high electrical efficiency of > 50% has been achieved in early tests and very useful waste heat is available from this high-temperature cell. 

Even for the intermediate-temperature SOFCs, Ni is the best anode as far as the current technological status is concerned. Although a number of investigations have been made on oxide anodes, nickel cermet (ceramic-metal) anodes exhibit... 

Refractory electronic-conducting ceramics may also provide candidate materials for the direct oxidation anode. Ceria and its solid solutions with other rare earths, cerates and titanates [46] have been investigated. Given their variation in conductivity with gas environment they may have to be used with metals in composites. The perovskites, of general formula ABO3, where A and B... 

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