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36-497: The abbreviation SOEC may refer to: Solid oxide electrolyser cell , a solid oxide fuel cell in regenerative mode. South Okanagan Events Centre , an indoor arena in Penticton, British Columbia. Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title SOEC . If an internal link led you here, you may wish to change

72-474: A {\displaystyle P_{O2}^{a}} is greater than P O 2 O x {\displaystyle P_{O2}^{Ox}} is dictated by whether ( ϕ O x {\displaystyle \phi ^{Ox}} - ϕ a {\displaystyle \phi ^{a}} ) or E a r e a R e {\displaystyle {\frac {E_{a}r_{e}^{a}}{R_{e}}}}

108-497: A {\displaystyle \phi ^{a}} are the electric potentials at the anode surface and the anode electrolyte interface respectively. In electrolysis mode ϕ O x {\displaystyle \phi ^{Ox}} > ϕ a {\displaystyle \phi ^{a}} and E a {\displaystyle E_{a}} > E N {\displaystyle E_{N}} . Whether P O 2

144-470: A solid oxide fuel cell . The net cell reaction yields hydrogen and oxygen gases. The reactions for one mole of water are shown below, with oxidation of oxide ions occurring at the anode and reduction of water occurring at the cathode . Anode: 2 O → O 2 + 4 e Cathode: H 2 O + 2 e → H 2 + O Net Reaction: 2 H 2 O → 2 H 2 + O 2 Electrolysis of water at 298 K (25 °C) requires 285.83 kJ of energy per mole in order to occur, and

180-644: A devices used in Mars Oxygen ISRU Experiment on the Perseverance rover as a means to produce oxygen for both human sustenance and liquid oxygen rocket propellant. In April 2021, NASA claimed it has successfully produced 1 gallon of earth-equivalent oxygen (4 and 5 grams of oxygen on Mars) from CO 2 in the Mars atmosphere. SOEC modules can operate in three different modes: exothermic, endothermic and thermoneutral . In exothermic mode,

216-478: A fuel electrode (cathode), an oxygen electrode (anode) and a solid-oxide electrolyte. The most common electrolyte, again similar to solid-oxide fuel cells, is a dense ionic conductor consisting of ZrO 2 doped with 8 mol-% Y 2 O 3 (also known as YSZ, ytrium-stabilized zirconia). Zirconium dioxide is used because of its high strength, high melting temperature (approximately 2700 °C) and excellent corrosion resistance. Yttrium(III) oxide (Y 2 O 3 )

252-418: A given fuel cell is usually optimized for operating in one mode and may not be built in such a way that it can be operated in reverse. Fuel cells operated backwards may not make very efficient systems unless they are constructed to do so such as in the case of solid oxide electrolyzer cells, high pressure electrolyzers , unitized regenerative fuel cells and regenerative fuel cells . However, current research

288-473: A material it dubbed Solar White that it is exploring for use as a radiator in deep space, where it is expected to reflect more than 99.9% of the sun’s energy (low solar radiation absorption and high infrared emittance). A sphere covered with a 10 mm coating sited far from the Earth and 1 astronomical unit from the sun could keep temperatures below 50 K. One use is long-term cryogenic storage. Yttrium Oxide

324-410: Is zirconium oxide which has been stabilized with the addition of yttrium oxide . The full name of zirconia used in dentistry is "yttria-stabilized zirconia" or YSZ. Yttrium oxide is also used to make yttrium iron garnets , which are very effective microwave filters. Y 2 O 3 is used to make the high temperature superconductor YBa 2 Cu 3 O 7 , known as "1-2-3" to indicate the ratio of

360-424: Is 27 W/(m·K). Yttrium oxide is widely used to make Eu:YVO 4 and Eu:Y 2 O 3 phosphors that give the red color in color TV picture tubes. Y 2 O 3 is a prospective solid-state laser material. In particular, lasers with ytterbium as dopant allow the efficient operation both in continuous operation and in pulsed regimes. At high concentration of excitations (of order of 1%) and poor cooling,

396-486: Is a Ni doped YSZ. However, high steam partial pressures and low hydrogen partial pressures at the Ni-YSZ interface causes oxidation of the nickel which results in catalyst degradation. Perovskite-type lanthanum strontium manganese (LSM) is also commonly used as a cathode material. Recent studies have found that doping LSM with scandium to form LSMS promotes mobility of oxide ions in the cathode, increasing reduction kinetics at

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432-403: Is added to mitigate the phase transition from the tetragonal to the monoclinic phase on rapid cooling, which can lead to cracks and decrease the conductive properties of the electrolyte by causing scattering. Some other common choices for SOEC are Scandia stabilized zirconia (ScSZ), ceria based electrolytes or lanthanum gallate materials. Despite the material similarity to solid oxide fuel cells,

468-469: Is being conducted to investigate systems in which a solid oxide cell may be run in either direction efficiently. Fuel cells operated in electrolysis mode have been observed to degrade primarily due to anode delamination from the electrolyte. The delamination is a result of high oxygen partial pressure build up at the electrolyte-anode interface. Pores in the electrolyte-anode material act to confine high oxygen partial pressures inducing stress concentration in

504-399: Is greater than ( E a − E N ) r i a R i {\displaystyle {\frac {(E_{a}-E_{N})r_{i}^{a}}{R_{i}}}} . The internal oxygen partial pressure is minimized by increasing the electronic resistance at the anode interface and decreasing the ionic resistance at anode interface. Delamination of

540-482: Is the applied voltage, E N {\displaystyle E_{N}} is the Nernst potential, R e {\displaystyle R_{e}} and R i {\displaystyle R_{i}} are the overall electronic and ionic area specific resistances respectively, and ϕ O x {\displaystyle \phi ^{Ox}} and ϕ

576-407: Is the oxygen partial pressure exposed to the oxygen electrode (anode), r e a {\displaystyle r_{e}^{a}} is the area specific electronic resistance at the anode interface, r i a {\displaystyle r_{i}^{a}} is the area specific ionic resistance at the anode interface, E a {\displaystyle E_{a}}

612-442: Is thermoneutral in which the heat generated through irreversible losses is equal to the heat required by the reaction. As there are some thermal losses, an external heat source is needed. This mode consumes more electricity than endothermic operation mode. Yttrium(III) oxide Yttrium oxide , also known as yttria , is Y 2 O 3 . It is an air-stable, white solid substance . The thermal conductivity of yttrium oxide

648-400: Is used to produce Yttrium Iron Garnets , which are very effective microwave filters. It's also used to create red phosphors for LED screens and TV tubes, as well as in anti-reflective coatings to enhance light transmission. Yttrium is required in production of Yttrium Aluminum Garnet (YAG) lasers, which are widely used in industrial and medical applications. Yttriaite-(Y) , approved as

684-560: The LSM lattice are being researched to optimize the properties of the LSMS cathode. New materials are being researched such as lanthanum strontium manganese chromate (LSCM), which has proven to be more stable under electrolysis conditions. LSCM has high redox stability, which is crucial especially at the interface with the electrolyte. Scandium-doped LCSM (LSCMS) is also being researched as a cathode material due to its high ionic conductivity. However,

720-733: The anode from the electrolyte increases the resistance of the cell and necessitates higher operating voltages in order to maintain a stable current. Higher applied voltages increases the internal oxygen partial pressure, further exacerbating the degradation. SOECs have possible application in fuel production, carbon dioxide recycling, and chemicals synthesis. In addition to the production of hydrogen and oxygen, an SOEC could be used to create syngas by electrolyzing water vapor and carbon dioxide. Mega-watt scale SOEC have been installed in Rotterdam, using industrial waste heat to reach its operating temperature of 850°C . In 2014 MIT successfully tested

756-481: The current density when operated at 800 °C. The increased performance is postulated to be due to higher "overstoichimoetry" of oxygen in the neodymium nickelate, making it a successful conductor of both ions and electrons. Advantages of solid oxide-based regenerative fuel cells include high efficiencies, as they are not limited by Carnot efficiency . Additional advantages include long-term stability, fuel flexibility, low emissions, and low operating costs. However,

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792-409: The dense electrolyte. The electrolyte must be dense enough that the steam and hydrogen gas cannot diffuse through and lead to the recombination of the H 2 and O . At the electrolyte-anode interface, the oxygen ions are oxidized to form pure oxygen gas, which is collected at the surface of the anode. Solid oxide electrolyzer cells follow the same construction of a solid-oxide fuel cell, consisting of

828-412: The electrolyzer cell is to split water in the form of steam into pure H 2 and O 2 . Steam is fed into the porous cathode. When a voltage is applied, the steam moves to the cathode-electrolyte interface and is reduced to form pure H 2 and oxygen ions. The hydrogen gas then diffuses back up through the cathode and is collected at its surface as hydrogen fuel, while the oxygen ions are conducted through

864-536: The flames of artificially-produced gases (initially hydrogen, later coal gas, paraffin, or other products) into human-visible light. This use is almost obsolete - thorium and cerium oxides are larger components of such products these days. Yttrium oxide is used to stabilize the Zirconia in late-generation porcelain-free metal-free dental ceramics. This is a very hard ceramic used as a strong base material in some full ceramic restorations. The zirconia used in dentistry

900-454: The greatest disadvantage is the high operating temperature , which results in long start-up times and break-in times. The high operating temperature also leads to mechanical compatibility issues such as thermal expansion mismatch and chemical stability issues such as diffusion between layers of material in the cell In principle, the process of any fuel cell could be reversed, due to the inherent reversibility of chemical reactions. However,

936-435: The interface with the electrolyte and thus leading to higher performance at low temperatures than traditional LSM cells. However, further development of the sintering process parameters is required to prevent precipitation of scandium oxide into the LSM lattice. These precipitate particles are problematic because they can impede electron and ion conduction. In particular, the processing temperature and concentration of scandium in

972-590: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=SOEC&oldid=813560853 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Solid oxide electrolyser cell Solid oxide electrolyzer cells operate at temperatures which allow high-temperature electrolysis to occur, typically between 500 and 850 °C. These operating temperatures are similar to those conditions for

1008-456: The metal constituents: This synthesis is typically conducted at 800 °C. Yttrium oxide is an important starting point for inorganic compounds. For organometallic chemistry it is converted to YCl 3 in a reaction with concentrated hydrochloric acid and ammonium chloride . Y 2 O 3 is used in specialty coatings and pastes that can withstand high temperatures and act as a barrier for reactive metals such as uranium. NASA developed

1044-439: The operating conditions are different, leading to issues such as high steam concentrations at the fuel electrode and high oxygen partial pressures at the electrolyte/oxygen electrode interface. A recent study found that periodic cycling a cell between electrolyzer and fuel cell modes reduced the oxygen partial pressure build up and drastically increased the lifetime of the electrolyzer cell. The most common fuel electrode material

1080-419: The quenching of emission at laser frequency and avalanche broadband emission takes place. (Yttria-based lasers are not to be confused with YAG lasers using yttrium aluminium garnet , a widely used crystal host for rare earth laser dopants). The original use of the mineral yttria and the purpose of its extraction from mineral sources was as part of the process of making gas mantles and other products for turning

1116-554: The rare-earth element introduces a significant materials cost and was found to cause a slight decrease in overall mixed conductivity. Nonetheless, LCSMS materials have demonstrated high efficiency at temperatures as low as 700 °C. Lanthanum strontium manganate (LSM) is the most common oxygen electrode material. LSM offers high performance under electrolysis conditions due to generation of oxygen vacancies under anodic polarization that aid oxygen diffusion. In addition, impregnating LSM electrode with Gd-doped CeO 2 (GDC) nanoparticles

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1152-452: The reaction is increasingly endothermic with increasing temperature. However, the energy demand may be reduced due to the Joule heating of an electrolysis cell, which may be utilized in the water splitting process at high temperatures. Research is ongoing to add heat from external heat sources such as concentrating solar thermal collectors and geothermal sources. The general function of

1188-451: The stack temperature increases during operation due to heat accumulation, and this heat is used for inlet gas preheating. Therefore, an external heat source is not needed while the electrical energy consumption increases. In the endothermic stack operation mode, there is an increase in heat energy consumption and a reduction in electrical energy consumption and hydrogen production because the average current density also decreases. The third mode

1224-421: The surrounding material. The maximum stress induced can be expressed in terms of the internal oxygen pressure using the following equation from fracture mechanics: where c is the length of the crack or pore and ρ {\displaystyle \rho } is the radius of curvature of the crack or pore. If σ m a x {\displaystyle \sigma _{max}} exceeds

1260-467: The theoretical strength of the material, the crack will propagate, macroscopically resulting in delamination. Virkar et al. created a model to calculate the internal oxygen partial pressure from the oxygen partial pressure exposed to the electrodes and the electrolyte resistive properties. The internal pressure of oxygen at the electrolyte- anode interface was modelled as: where P O 2 O x {\displaystyle P_{O2}^{Ox}}

1296-404: Was found to increase cell lifetime by preventing delamination at the electrode/electrolyte interface. The exact mechanism by how this happen needs to be explore further. In a 2010 study, it was found that neodymium nickelate as an anode material provided 1.7 times the current density of typical LSM anodes when integrated into a commercial SOEC and operated at 700 °C, and approximately 4 times

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