Hydrogen solid oxide fuel cell

The principle of the fuel cell was first demonstrated by Grove in 1839 [W. R. Grove, Phil. Mag. 14 (1839) 137]. Today, different schemes exist for utilizing hydrogen in electrochemical cells. We explain the two most important, namely the Polymer Electrolyte Membrane Fuel Cell (PEMFC) and the Solid Oxide Fuel Cell (SOFC). 

The use of this approach can be illustrated by the perovskite structure proton conductor BaYo.2Zro.gO3 g- This material has been investigated for possible use in solid oxide fuel cells, hydrogen sensors and pumps, and as catalysts. It is similar to the BaPr03 oxide described above. The parent phase is Ba2+Zr4+03, and doping with... 

During the course of the last century, it was realized that many properties of solids are controlled not so much by the chemical composition or the chemical bonds linking the constituent atoms in the crystal but by faults or defects in the structure. Over the course of time the subject has, if anything, increased in importance. Indeed, there is no aspect of the physics and chemistry of solids that is not decisively influenced by the defects that occur in the material under consideration. The whole of the modem silicon-based computer industry is founded upon the introduction of precise amounts of specific impurities into extremely pure crystals. Solid-state lasers function because of the activity of impurity atoms. Battery science, solid oxide fuel cells, hydrogen storage, displays, all rest upon an understanding of defects in the solid matrix. 

Leng YJ, Chan SH, Khor KA, and Jiang SP. Performance evaluation of anode-supported solid oxide fuel cells with thin-film YSZ electrolyte. Int J Hydrogen Energy 2004 29 1025-1033. 

Galea NM, Kadantsev ES, and Ziegler T. Studying reduction in solid oxide fuel cell activity with density functional theory-effects of hydrogen sulfide adsorption on nickel anode surface. JPhys Chem C 2007 111 14457-14468. 

Yates C and Winnick J. Anode materials for a hydrogen sulfide solid oxide fuel cell. J Electrochem Soc 1999 146 2841-2844. 

Aguilar L, Zha S, Cheng Z, Winnick J, and Liu M. A solid oxide fuel cell operating on hydrogen sulfide (H2S) and sulfur-containing fuels. J Power Sources 2004 135 17-24. 

Hydrogen aircraft have been studied by NASA. This involved a fuel-cell-powered aircraft the size of a Boeing 737 in its Revolutionary Aeropropulsion Concepts program. The hydrogen 737 would use a solid oxide fuel cell (SOFC) for power. 

A 2002 study for the National Energy Technology Laboratory found that coal gasification systems with C02 capture could reach efficiencies of 60% or more in cogenerating hydrogen and electricity using different configurations of turbines and solid oxide fuel cells (SOFCs). 

For natural-gas-fuelled CHP plants, the same line of argumentation holds as for the stationary use of hydrogen from biomass. It is more reasonable to use natural gas directly than to convert it to hydrogen first and then to heat and electricity. High electrical efficiencies can be reached in the stationary sector by feeding natural gas to molten-carbonate fuel cells (MCFC) and solid-oxide fuel cells (SOFC). Molten-carbonate fuel cells have the added advantage of using C02 for the electrolyte (see also Chapter 13). 

In fuel cells, the combustion energy of hydrocarbons can be converted directly into electrical energy. At the fuel cell anode, the hydrocarbon is in most cases converted to carbon dioxide because the intermediates are more easily oxidized than the starting hydrocarbon (Eq. 9a) at the fuel cell cathode oxygen is reduced to water (Eq. 9b). Most fuel cell research has involved the use of hydrogen as fuel. However, solid oxide fuels cells (SOCFs) can operate at higher temperature and can... 

In a similar study, Liebhafsky and Cairns (31) compared two arrangements of tubular, calcia-stabilized solid oxide fuel cells. In one arrangement, hydrogen and air were supplied to a single. 

The purpose of the present review is to summarize the current status of fundamental models for fuel cell engineering and indicate where this burgeoning field is heading. By choice, this review is limited to hydrogen/air polymer electrolyte fuel cells (PEFCs), direct methanol fuel cells (DMFCs), and solid oxide fuel cells (SOFCs). Also, the review does not include microscopic, first-principle modeling of fuel cell materials, such as proton conducting membranes and catalyst surfaces. For good overviews of the latter fields, the reader can turn to Kreuer, Paddison, and Koper, for example. 

A solid oxide fuel cell is an electrochemical device which converts the Gibbs free enthalpy of the combustion reaction of a fuel and an oxidant gas (air) as far as possible directly into electricity. Hydrogen and oxygen are used to illustrate the simplest case. This allows the calculation of the reversible work for the reversible reaction. Heat must be transferred reversibly as well to the surrounding environment in this instance. 

Andreassi L., Bove R., Rubeo G., Ubertini S., Lunghi P., 2007. Experimental and numerical analysis of a radial flow Solid Oxide Fuel Cell. International Journal of Hydrogen Energy 32(17), 4559 1574. 

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