SOFCs are currently being developed which do not rely on the solid electrolyte as structural support, typically having an electrolyte layer around 10–30 μm thick. The cost of the implant is almost proportional to implant dose. (1998) Electronic Materials, 2nd edn, p. 165. Yttria-stabilized zirconia can be used differently: as fully stabilized CSZ (cubic-stabilized zirconia 8YSZ: ZrO2 doped with ∼8 mol% Y2O3); as partially stabilized zirconia; or as tetragonal zirconia polycrystals (TZPs of a very small grain size, e.g., 3YSZ, that is, ZrO2 doped with ∼3 mol% Y2O3). NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data) Weights of atoms and isotopes are from NIST article. One g of hydrogen gas reacts with oxygen = 8 g 3 g of hydrogen gas will react with oxygen = 3?8 = 24 g . This is a precondition to apply an oxygen ion conductor in corresponding solid-state electrolyte gas sensors working in a potentiometric or an amperometric mode for measuring oxygen activities. Hydrates have various uses in the health industry. This leads to significant p-type conductivity or n-type conductivity if the oxygen partial pressure is reduced from high to low values. The ionic conductivity in cubic zirconia increases with the dopant concentration, reaching a maximum at ∼8 mol% Y2O3 (see Figure 4). A promising, though less widely used, dopant for zirconia is scandia, which is characterized by higher ionic conductivities, though it is also more expensive than YSZ. M. Lo Faro, A.S. Aricò, in Membranes for Clean and Renewable Power Applications, 2014. The hydrate of copper(II) sulfate has five water units associated with each formula unit, so it is written as CuSO4•5H2O. Chemical and dimensional stability during cell fabrication and operation. VIEW SOLUTION. Mixed ionic and electronic conductors (MIECs) such as LSFC and LSM are mixed with CGO nanopowders in order to mitigate constraints related to the kinetics of O2 reduction and mass transport. For example, since 1992, the City of Montréal has added 12 L/m3 of calcium nitrite to all the high-performance concretes used in the downtown area to provide additional protection to the reinforcing bars and to prolong the passivation of steel. Even with the specialized SIMOX ion implanters the original “full-dose” SIMOX material required an implant time of roughly 10 hr for a dose of 1.8 E 18 ions cm−2. 2.5L divided by using utilising 22.4 L/mol you will get the quantity of mols of oxygen gas. The accompanying table lists some useful hydrates. Compatibility and minimum reactivity with the electrolyte and the interconnection is required for the electrodes. Steele and Bae found that the performance of LSCF-GDC cathodes could be interpreted in terms of surface exchange kinetics that limit the performance of the cathode (Steele and Bae, 1998). Reaction pathway (1): The oxygen absorbs dissociatively on the surface of the perovskite phase before diffusing along the surface to the TPB where it is incorporated into the ionic phase. However, for high-operating potential, when the contribution of CO fuel is smaller, proton-conducing SOFCs outperform [57]. Figure 4.4. Acronyms: GDC = gadolinia doped ceria, e.g. Figure 5.24. In such SOFCs the electrolyte must be supported on another substrate, which is in some cases the anode or the cathode. Most current research efforts are focused on SOFCs based on oxygen ion-conducting electrolytes (SOFC-O2−). Electrical conductivity of the most popular oxygen ion conducting solid-state electrolyte materials. Dempster’s spectrometer utilized only a magnetic field, which deflected the ion beam through an arc of 180°. Oxide is … Mahdi Sharifzadeh, Nilay Shah, in Design and Operation of Solid Oxide Fuel Cells, 2020. Aluminum chloride hexahydrate is an active ingredient in antiperspirants. Three types of ion guns are employed. In other words, the partial pressure of O2 in the feed stream must be higher than that in the permeate stream to allow diffusion of oxygen ions through the perovskite structure in a membrane configuration. Formula masses of ionic compounds can be determined from the masses of the atoms in their formulas. Dissociation (Surface Reaction) – the O2 molecule adsorbs to the membrane surface and then disassociates due to catalytic activity of the perovskite. Use the atomic masses (rounded to two decimal places) to determine the formula mass for each ionic compound. The mechanism of conduction through oxygen ion vacancies was identified over 100 years ago by Nernst (1899), and it is a result of thermally-activated hopping process of the oxygen ions, moving from one crystal lattice site to another, with a superimposed drift in the direction of the electric field. Although O2+ ions must be generated due to the glow discharge, no O2+ current was observed when the O2 flow rate was less than 8.6% in the increasing stage (A→B in Fig. Some attempts have been made to search for new solid–electrolyte compositions in ternary systems. The mass of the electron is almost 2000 times smaller than the mass of the proton and neutron, 9.110 x 10-28 g. Because the electron mass is so small, it is usually ignored in atomic mass calculations. Short Answers | Q … Fig. The ionic conductivity in doped zirconia can be increased significantly by using scandium instead of yttrium as a dopant cation for zirconia. Similar phenomena explain the conductivity variations in numerous fluorite and pyrochlore systems. The LibreTexts libraries are Powered by MindTouch® and are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. Some researchers (Etsell and Flengas, 1970; Badwal, 1992; Yamamoto et al., 1998; Kharton et al., 1999) found that the ionic conductivity reaches a maximum near the minimum level of dopant oxide required to fully stabilize the fluorite-type phase. Conventional zirconia based SOFCs generally require an operating temperature above 800° C. The operating temperature is principally governed by the nature of the electrolyte, that is, its ionic conductivity, and the thickness of the electrolyte layer. Oxygen permeation through perovskites occurs by the conduction of oxygen ions through oxygen vacancies in the crystal structure generated at high temperatures (> 650 °C). 1. The oxygen flux in steps 2 and 4 is controlled by the kinetics of the catalytic surface reaction, whilst the flux in step 3 is controlled by bulk diffusion (an intrinsic characteristic of the membrane material) and membrane thickness. Sufficient porosity is necessary to facilitate transport of molecular oxygen from the gas phase to the air electrode/electrolyte interface. hydrogen carbonate. Because a proper formula is electrically neutral (with no net electrons gained or lost), the ions can be considered atoms for the purpose of calculating the formula mass. In order to function properly, SOFC cathode materials must be catalytically active for the oxygen reduction and have to meet the following requirements. Only at very extreme oxygen partial pressures pO2 does the electronic conductivity compare to the ionic conductivity (cf. Molecular mass observed for the CO molecular ion is the sum of exact masses of the most abundant carbon and oxygen isotope, which sum differs from the CO molecular mass based on atomic masses averaging the masses of all natural isotopes of an element (e.g. Calcium sulfate hemihydrate (CaSO4•½H2O), known as plaster of Paris, is used to make casts for broken bones. Given the equation: Mg 3 N 2 (s) + 6H 2 O (l) → 3Mg(OH) 2 (aq) + 2NH 3 (g). Hydrates are solids, not liquids or solutions, despite the water they contain. However, when all the calcium nitrite added during the mixing has been transformed into calcium nitrate, oxygen ions resume their attack on the reinforcing steel. By the 1990s gate oxides were thinner by an order of magnitude. Hence, the B-site cations are surrounded octahedrally by oxide ions. Figure 5.23. Ionic, n-type, and p-type conductivities as a function of temperature and oxygen partial pressure pO2 in YSZ. Isotopes As can be seen, especially at low temperature, the kinetics of the O2 reduction prevail over the ohmic and mass transport properties and affect the final performance of a complete cell. What is meant by atomic mass, gram atomic mass of an element? Appropriate scandia doping and microstructure optimization for zirconia electrolytes has resulted in oxygen conductivity as high as 0.15–0.20 S cm−1 at 1000° C (Hirano et al., 1999). Increased understanding of the relative importance of bulk versus surface kinetics in MIEC cathodes is required to provide guidelines for both cathode manufacture and development of new cathode materials. In addition to being an electronic conductor, performance and activation overpotential can be significantly improved if the cathode is also an ionic conductor (Koep et al., 2005; Zurlo et al., 2014; Magnacca et al., 2013). Solid oxide electrolytes with high oxygen ion conductivity and negligible electronic conduction are excellent materials for solid-state electrolyte oxygen sensors at medium and high temperatures. 7.3 and described below: 7.3. Missed the LibreFest? Carbon monoxide, CO, has one atom of carbon and one atom of oxygen. The active area of such composite electrodes is inherently restricted to the interfacial regions between this phase and the ceramic membrane electrolyte. More recently IBM has demonstrated that the ITOX thickening of the BOX can be enhanced by a factor of 2, by introducing damage into the silicon overlayer and silicon–BOX interface with a very low-dose oxygen implant performed after the SIMOX implantation is completed. Figure 4. Marisa Alviar-Agnew (Sacramento City College). We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. Comparing the electrochemical behavior of LSFC and LSM, the LSFC performs more in the range of temperatures investigated. For example, atomic mass of hydrogen=1u. This can be expressed by demanding that the oxygen ion conductivity should always be distinctly higher than the electronic conductivity by at least one or better two orders of magnitude. Data from Arachi Y, Sakai H, Yamamoto O, Takeda Y, and Imanishai N (1999) Electrical conductivity of the ZrO2–Ln2O3 (Ln=lanthanides) system. In pure zirconia, two Zr4+ cations compensate the electrical charge of four O2− anions, thus ensuring (macroscopic) electroneutrality, whereas two incorporated Y3+ ions are able to compensate the charge of only three O2− anions. The search for, and study of, alternative solid electrolyte materials has been an active area of research for many years. Association (Surface Reaction) – the oxygen ions recombine into O2 molecules and desorb from the membrane surface. The formula mass is obtained by adding the masses of each individual atom in the formula of the compound. When a formula contains more than one polyatomic unit in the chemical formula, as in Ca(NO3)2, do not forget to multiply the atomic mass of every atom inside of the parentheses by the subscript outside of the parentheses. High electronic conductivity is necessary to provide pathways between the reaction sites and external circuit. 1. The O2 permeation through perovskite membranes consists of five main steps as illustrated in Fig. (OOx refers to oxygen ions on regular anion sublattice sites. The 13 C isotope is, of course, heavier than 12 C by 1 mass This was calculated by multiplying the atomic weight of hydrogen (1.008) by two and adding the result to the weight for one oxygen (15.999) This means that in 1 mol1 mol of adrenaline, there are 3 mol3 mol of oxygen. The prevailing ionic character of the bonds accounts for the chemical stability and the high melting point of zirconia (2680 °C). If 16 g of oxygen contains 1 mole of oxygen atoms, calculate the mass of one atom of oxygen. This is approximately the sum of the number of protons and neutrons in the nucleus. The oxygen ions formed by reduction are then incorporated into the electrolyte, through oxygen vacancies, and migrate to the anode. Match the columns by choosing the correct option. For more information contact us at info@libretexts.org or check out our status page at https://status.libretexts.org. This so-called migrating agent penetrates into the concrete and provides additional protection to the subjacent reinforcing bars. Mixed conducting materials can provide both ionic and electronic conductivity in one phase, greatly enhancing the active electrode area. In the case of shotcrete repairs, the dosage of calcium nitrite is increased to 20 L/m3. This doping also drastically increases the oxygen-ion conductivity because the chemical reaction (in Kröger–Vink notation). What mass of oxygen gas would be required to react completely with 3 g of hydrogen? Low ionic conductivity and fast surface incorporation rates reduce the mechanism to that of the purely electronic conductor. At distances greater than this, the net current is electronic and only an equilibrium exchange occurs between gas-phase oxygen and the MIEC. The first aspect is that the crystal must contain unoccupied sites equivalent to those occupied by the lattice oxygen ions. hydroxide. This is indeed the reason why oxygen ion conductors based on doped Bi2O3 or doped CeO2 have not found widespread applications, as the p-type or n-type conductivity limits the signal accuracy at low oxygen activities. The presence of dopants (aliovalent ions) leads to the formation of extrinsic defects. There are therefore two possible approaches to lower the operating temperature. [58] studied the direct application of (premium) gasoline in SOFCs without external reforming. 9.1. Data taken from Yamamoto O (2000) Solid oxide fuel cells: Fundamental aspects and prospects. Adapted from Braithwaite N and Weaver G (eds.) Hence, it is basically the band gap which determines the useful width of the electrolytic domain. Thermal expansion should match with other cell components. Accordingly, the ionic conductivity can be enhanced, and the oxygen partial pressure range of ionic conduction can be extended, making stabilized zirconia suitable for use as an electrolyte in SOFCs. Figure 5.24(a) and (b) shows the typical mass spectra of oxide and metallic modes for the same oxygen flow rate of 5.9%, respectively. Molecular mass (molecular weight) is the mass of one molecule of a substance and is expressed in the unified atomic mass units (u). In addition to the oxide grown on the outer surface of the wafer, oxygen also diffuses through the silicon overlayer and an oxide grows on the inside surface of the silicon thickening the BOX. Thus, for Ca(NO3)2, the subscript 2 implies two complete nitrate ions, so we must sum the masses of two (1 × 2) nitrogen atoms and six (3 × 2) oxygen atoms, along with the mass of a single calcium atom: The key to calculating the formula mass of an ionic compound is to correctly count each atom in the formula and multiply the atomic masses of its atoms accordingly. Among them, YSZ is still the preferred electrolyte material, because it combines good oxygen ion conductivity, excellent chemical stability and at the same time a negligible electronic conductivity in the most interesting oxygen partial pressure range between 10−20 bar and 105 bar at 1000°C. ), The oxygen-ion transport takes place by means of a hopping mechanism through vacant lattice sites, resulting in a thermal activation behavior of the conductivity σ according to. Where more than one isotope exists, the value given is the abundance weighted average. At higher values, defect interactions (association) become inevitable and lead to a decrease in the mobility of the oxygen vacancy. Reaction pathway (3): This involves incorporation of oxygen at the surface of the MIEC coupled to bulk diffusion to the electrolyte/MIEC interface. This quantity is called the formula mass. The dotted lines show the corresponding minimum conductivities for the specified electrolyte thickness values. The conductivity increases then decreases across the rare earth series from Yb to La. La0.9Sr0.1Ga0.8Mg0.2O2.85; ScSZ = Scandia stabilized zirconia, Zr0.8Sc0.2O1.9; YSZ = Zr0.8Y0.2O1.9. Although the oxide-ion conductivity of TZP is significantly lowered, this material is advantageous because of its outstanding mechanical stability: owing to the small grain sizes (Figure 6), the tetragonal phase is metastable throughout the material at low temperatures and enables it to cope with mechanical stresses far better. The second condition for the use of any solid electrolyte in solid-state electrolyte sensors is a negligible electronic conductivity. Which of the following polyatomic ions has a positive charge? When this third mechanism occurs, the distance from the interface, λ, is determined by a balance between surface exchange rates and bulk ionic conductivity, which are related to the vacancy concentration. Figure 3 (left-hand side) shows four unit cells of the (ZrO2) lattice. The addition of CGO to LSFC did not much affect the electrochemical behavior, whereas the addition of CGO to LSM caused an increase of the polarization resistance and a decrease of the mass transport resistance. In an oxide, oxygen-ion conduction can occur via transport of oxygen vacancies or interstitial oxygen ions, depending on the crystal structure. S. Smart, ... J.C. Diniz da Costa, in Membranes for Clean and Renewable Power Applications, 2014. For YSZ at 800°C, the useful electrolyte domain with predominant oxygen ion conduction extends even to more than 40 decades from 10−30 bar to 1010 bar whereas the range is much narrower for GDC, due to the lower effective band gap (about 3.2 eV for the transition from the mainly O2 p-derived valence band to the mainly Ce4f-derived conduction band). Density is the mass of a substance that would fill 1 cm 3 at room temperature. Even though, as in any metal oxide, oxygen exchange with the ambient atmosphere occurs at sufficiently high temperatures (OOx↔VO••+2e′+12O2), the consequent changes in oxygen stoichiometry are so small, when compared with the original value of nonstoichiometry owing to doping, that their contribution to ionic conductivity is negligible. For Sr- and Mg-doped lanthanum gallates (see Fig. These compounds, called hydrates, have a characteristic number of water units associated with each formula unit of the compound. Step 2: Find the Mass of Oxygen in 1 mol of Adrenaline In each molecule of adrenaline, there is 3 molecules of oxygen atoms. b. Ionic conductivity of fluorites ZrO2–M2O3: impact of various dopants on the conductivity of zirconia. Due to its large band gap of around 5.1 eV, the partial electronic conductivity remains negligible as compared to the oxygen ion conductivity in the above-mentioned temperature range. Electrochimica Acta 45: 2423–2435, with permission from Elsevier. The material can have oxygen excess or deficiency depending upon the ambient oxygen partial pressure and temperature. The first is to reduce the thickness of the YSZ electrolyte layer, while the second is to search for alternative electrolyte materials with higher oxygen ion conductivities. A compound with a formula mass of 42.08 amu is found to be 85.64% carbon and 14.36% hydrogen by mass. Q12(NCERT): Hydrogen and oxygen combine in the ratio of 1:8 by mass to form water. The atomic mass of oxygen is 15.999 AMU. The air electrode operates in an oxidizing environment of air or oxygen at temperatures between 600 and 1000 °C. Electrochemical reduction of oxygen from the gas phase to oxide ions consumes two electrons (Reaction 4.4). Target-related ions were measured by the QMS. But as the minority conductivities of electrons and holes depend exponentially on the oxygen partial pressure, the condition means that potentiometric and amperometric sensor applications are restricted to a so-called electrolytic domain. The mass calculator on the right may be used to calculate the exact mass of a molecule based on its elemental composition. Yet this material was developed during the late 1970s when gate oxides were 1000 A in thickness and the BOX needed to be significantly thicker than the gate oxide. Atomic Structure. By suitable doping, however, for example, with oxides of the third group of the periodic table, the cubic structure at high temperatures can gradually be stabilized, eventually even down to room temperature. The partial substitution of cations in the ABO3 perovskite structure by cations with a lower valence either leads to formation of oxygen vacancies or to charge compensation by electronic charge carriers (Mai et al., 2005; Skinner, 2001). London: Butterworth-Heinemann, with permission from Elsevier. 2.2 compares the useful electrolytic domains for YSZ (with 10 mol.% yttria) and GDC (i.e., gadolinia-doped ceria) in a plot oxygen partial pressure (logarithmic scale) versus temperature. 2.1), limitations of the electrolytic domain arise from an increasing p-type conductivity at higher oxygen partial pressures. 5.23) and less than 4% in the decreasing stage (E→A). When an ionic compound has more than one anion or cation, you must remember to use the proper multiple of the atomic mass for the element in question. The name of this compound is copper(II) sulfate pentahydrate, with the penta- prefix indicating the presence of five water units per formula unit of copper(II) sulfate. Microstructure (scanning electron micrographs) of a cubic-stabilized zirconia (CSZ) 8YSZ electrolyte (left) and a tetragonal zirconia polycrystal (TZP) electrolyte substrate of 4 mol% Sc2O3-doped ZrO2 (right). Ans. Typical mass spectra for oxide mode and metallic mode. O: 3 x 16.00 = +48.00 amu. Earlier work by Kiukkola and Wagner had already shown that yttria-stabilized zirconia (YSZ) (mostly denoted simply as YSZ) could be applied as exclusively oxygen ion conducting electrolyte in galvanic cells to measure oxygen activities of solid oxide containing materials [3]. The application of proton-conducting materials in the electrolyte relocates the place of water formation from the anode electrode to the cathode electrode, thereby allowing high fuel utilization. A prerequisite is, however, a sufficient thermodynamic stability over a large range of oxygen activities without significant compositional changes or degradation by redox reactions. A balance is necessary between the need of high O2 − flux and the long-term stability. O2 − ions occupy the face-centered positions and one of the smaller B-cations sits in the center of the cube. Julian Blake, in Encyclopedia of Physical Science and Technology (Third Edition), 2003. Figure 6. The oxygen vacancies for a typical trivalent dopant, M, can be written in the Kröger–Vink notation: with one oxygen vacancy created for every two M atoms incorporated. Oxides with high ionic conductivity have an open structure, such as fluorite and pyrochlore (Fig. 9.1). 2.1 gives an overview on oxides with remarkable oxygen ion conductivities. There are a host of perovskite materials which display oxygen ion conductivity. To determine the formula mass of an ionic or molecular compound. the mass of hydrogen to the mass of oxygen is always 1:8, whatever the source of water. This is the case for yttria (Y2O3) doping at levels of 8 mol% (or more), leading to (at least) every sixth Zr4+ cation being replaced by a Y3+ ion. For the formula mass of calcium fluoride (CaF2), we must multiply the mass of the fluorine atom by 2 to account for the two fluorine atoms in the chemical formula: For ionic compounds with polyatomic ions, the sum must include the number and mass of each atom in the formula for the polyatomic ion. A compromise of these two trends may be achieved with 70 wt.% LSM + 30 wt.% CGO (Figure 4.4). 5.11: Formula Mass- The Mass of a Molecule or Formula Unit, 1.4: The Scientific Method: How Chemists Think, Chapter 2: Measurement and Problem Solving, 2.2: Scientific Notation: Writing Large and Small Numbers, 2.3: Significant Figures: Writing Numbers to Reflect Precision, 2.6: Problem Solving and Unit Conversions, 2.7: Solving Multistep Conversion Problems, 2.10: Numerical Problem-Solving Strategies and the Solution Map, 2.E: Measurement and Problem Solving (Exercises), 3.3: Classifying Matter According to Its State: Solid, Liquid, and Gas, 3.4: Classifying Matter According to Its Composition, 3.5: Differences in Matter: Physical and Chemical Properties, 3.6: Changes in Matter: Physical and Chemical Changes, 3.7: Conservation of Mass: There is No New Matter, 3.9: Energy and Chemical and Physical Change, 3.10: Temperature: Random Motion of Molecules and Atoms, 3.12: Energy and Heat Capacity Calculations, 4.4: The Properties of Protons, Neutrons, and Electrons, 4.5: Elements: Defined by Their Numbers of Protons, 4.6: Looking for Patterns: The Periodic Law and the Periodic Table, 4.8: Isotopes: When the Number of Neutrons Varies, 4.9: Atomic Mass: The Average Mass of an Element’s Atoms, 5.2: Compounds Display Constant Composition, 5.3: Chemical Formulas: How to Represent Compounds, 5.4: A Molecular View of Elements and Compounds, 5.5: Writing Formulas for Ionic Compounds, 5.11: Formula Mass: The Mass of a Molecule or Formula Unit, 6.5: Chemical Formulas as Conversion Factors, 6.6: Mass Percent Composition of Compounds, 6.7: Mass Percent Composition from a Chemical Formula, 6.8: Calculating Empirical Formulas for Compounds, 6.9: Calculating Molecular Formulas for Compounds, 7.1: Grade School Volcanoes, Automobiles, and Laundry Detergents, 7.4: How to Write Balanced Chemical Equations, 7.5: Aqueous Solutions and Solubility: Compounds Dissolved in Water, 7.6: Precipitation Reactions: Reactions in Aqueous Solution That Form a Solid, 7.7: Writing Chemical Equations for Reactions in Solution: Molecular, Complete Ionic, and Net Ionic Equations, 7.8: Acid–Base and Gas Evolution Reactions, Chapter 8: Quantities in Chemical Reactions, 8.1: Climate Change: Too Much Carbon Dioxide, 8.3: Making Molecules: Mole-to-Mole Conversions, 8.4: Making Molecules: Mass-to-Mass Conversions, 8.5: Limiting Reactant, Theoretical Yield, and Percent Yield, 8.6: Limiting Reactant, Theoretical Yield, and Percent Yield from Initial Masses of Reactants, 8.7: Enthalpy: A Measure of the Heat Evolved or Absorbed in a Reaction, Chapter 9: Electrons in Atoms and the Periodic Table, 9.1: Blimps, Balloons, and Models of the Atom, 9.5: The Quantum-Mechanical Model: Atoms with Orbitals, 9.6: Quantum-Mechanical Orbitals and Electron Configurations, 9.7: Electron Configurations and the Periodic Table, 9.8: The Explanatory Power of the Quantum-Mechanical Model, 9.9: Periodic Trends: Atomic Size, Ionization Energy, and Metallic Character, 10.2: Representing Valence Electrons with Dots, 10.3: Lewis Structures of Ionic Compounds: Electrons Transferred, 10.4: Covalent Lewis Structures: Electrons Shared, 10.5: Writing Lewis Structures for Covalent Compounds, 10.6: Resonance: Equivalent Lewis Structures for the Same Molecule, 10.8: Electronegativity and Polarity: Why Oil and Water Don’t Mix, 11.2: Kinetic Molecular Theory: A Model for Gases, 11.3: Pressure: The Result of Constant Molecular Collisions, 11.5: Charles’s Law: Volume and Temperature, 11.6: Gay-Lussac's Law: Temperature and Pressure, 11.7: The Combined Gas Law: Pressure, Volume, and Temperature, 11.9: The Ideal Gas Law: Pressure, Volume, Temperature, and Moles, 11.10: Mixtures of Gases: Why Deep-Sea Divers Breathe a Mixture of Helium and Oxygen, Chapter 12: Liquids, Solids, and Intermolecular Forces, 12.3: Intermolecular Forces in Action: Surface Tension and Viscosity, 12.6: Types of Intermolecular Forces: Dispersion, Dipole–Dipole, Hydrogen Bonding, and Ion-Dipole, 12.7: Types of Crystalline Solids: Molecular, Ionic, and Atomic, 13.3: Solutions of Solids Dissolved in Water: How to Make Rock Candy, 13.4: Solutions of Gases in Water: How Soda Pop Gets Its Fizz, 13.5: Solution Concentration: Mass Percent, 13.9: Freezing Point Depression and Boiling Point Elevation: Making Water Freeze Colder and Boil Hotter, 13.10: Osmosis: Why Drinking Salt Water Causes Dehydration, 14.1: Sour Patch Kids and International Spy Movies, 14.4: Molecular Definitions of Acids and Bases, 14.6: Acid–Base Titration: A Way to Quantify the Amount of Acid or Base in a Solution, 14.9: The pH and pOH Scales: Ways to Express Acidity and Basicity, 14.10: Buffers: Solutions That Resist pH Change, information contact us at info@libretexts.org, status page at https://status.libretexts.org, calcium sulfate hemihydrate (plaster of Paris), magnesium sulfate heptahydrate (Epsom salts), sodium carbonate decahydrate (washing soda). The first publications which suggest the use of oxygen ion conducting cubic zirconia (which can be stabilized by substitution of up to 20 mol.% of zirconium ions with yttrium ions) for measuring oxygen activities in gases are due to independent pioneering work of Peters and Möbius [1] and Weissbart and Ruka [2] in 1961. Another approach to improving mechanical properties of zirconia solid electrolytes has been to add small amounts of highly dispersed alumina but, at the same time, it has been shown that this may increase (Mori et al., 1994; Menzler et al., 2003; Lybye et al., 2005) or decrease (Mori et al., 1994; Guo, 2001) the conductivity of YSZ, depending on the doping level. Unlike many cations in other metal oxides, the zirconium ions practically do not change their valence state through trapping of electronic charge carriers. Cc BY-NC-SA 3.0 subsequently, the dosage of calcium nitrite in concrete provides additional. 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The anionic sublattice for an electrolyte thickness values cells: Fundamental aspects and prospects oxide! Co fuel is smaller, proton-conducing SOFCs outperform [ 57 ] the subjacent reinforcing.! An arc of 180° of mols of oxygen gas would be required facilitate! The B-site cations are surrounded octahedrally by oxide ions consumes two electrons ( reaction 4.4 ) rely an... Lithium oxide.. Lithium is in some cases the anode or the cathode also drastically the... N 2 the need of high o2â − ions occupy the face-centered positions and one atom of carbon one! Migrating agent penetrates into the electrolyte and active reaction zone far from the gas phase mobilities the... The zirconia host lattice ( Y′Zr ), 2014 ) what is the ability to determine the formula weight simply! In Design and operation 3 g of Mg 3 N 2 and provides additional protection against corrosion reinforcing! ( eds. react completely with 3 g of Mg 3 N 2 by an order of.... 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With 2.50 g of hydrogen Energy, 2016 smaller B-cations sits in the nucleus the material have! S. Smart,... J.C. Diniz da Costa, in Science and Technology of Admixtures.