WO1988004108A2 - Solid compositions for fuel cells, sensors and catalysts - Google Patents
Solid compositions for fuel cells, sensors and catalysts Download PDFInfo
- Publication number
- WO1988004108A2 WO1988004108A2 PCT/US1987/002881 US8702881W WO8804108A2 WO 1988004108 A2 WO1988004108 A2 WO 1988004108A2 US 8702881 W US8702881 W US 8702881W WO 8804108 A2 WO8804108 A2 WO 8804108A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- composite
- electrolyte
- independently selected
- formula
- lanthanum
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/403—Cells and electrode assemblies
- G01N27/406—Cells and probes with solid electrolytes
- G01N27/407—Cells and probes with solid electrolytes for investigating or analysing gases
- G01N27/4073—Composition or fabrication of the solid electrolyte
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/002—Mixed oxides other than spinels, e.g. perovskite
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/06—Halogens; Compounds thereof
- B01J27/08—Halides
- B01J27/12—Fluorides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/024—Multiple impregnation or coating
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
- H01M8/124—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2523/00—Constitutive chemical elements of heterogeneous catalysts
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Definitions
- the present invention relates to materials and processes to prepare polycrystal and monocrystal forms for use in fuel cells in sensors and as catalysts.
- a fuel cell having oxygen/solid lanthanum fluoride (as a single crystal)/hydrogen configuration produces about 1 volt of open circuit potential at essentially ambient temperature.
- specific mixed lanthanide or alkaline earth fluorides also produce electricity at moderate temperatures.
- Embodiments also include a porous perovskite-type metallic transition metal oxide electrode and a lanthanum metal/alkaline earth/fluoride electrolyte which are useful as a solid electrode/electrolyte in a fuel cell, as a sensor, or as a catalyst.
- Fuel cells convert chemical energy to electrical energy directly, without having a Carnot-cycle efficiency limitation, through electrochemical oxidation-reduction reactions of fuels.
- Several types of fuel cells have been or are being investigated at the present time. These may generally be classified as shown in Figure 1, as Table 1, depending upon the kinds of electrolyte used and the operation temperature.
- the solid electrolyte fuel cell which can be considered as the third generation fuel cell technology, is essentially an oxygen-hydrogen (or H 2 -CO mixture) fuel cell operated at high temperature (ca. 1000°C) with a solid ceramic oxide material used as the electrolyte.
- yttrium- or calcium-stabiifzed zirconium oxides have been used as the electrolyte.
- the mechanism of ionic conduction is oxygen ion transport via O 2- anion in the solid oxide crystal lattice.
- G.W. Mellors in European Patent Application No. 055,135 discloses a composition which can be used as a solid state electrolyte comprising at least 70 mole percent of cerium trifluoride and/or lanthanum trifluoride an alkaline earth metal compound e.g. fluoride, and an alalki metal compound e.g. lithium fluoride.
- the electrolyte composition is invariant and independent of the composition of the fuel and oxidant streams.
- sol id electrolyte fuel ceils demand less feed gas preparation than the phosphoric acid cell (see Figure 1 ) , which requires a conversion of CO to H 2 via the water-gas shift reaction , or the rnoiten carbonate cell (see Figure 1 ) , which requires a carbon dioxide loop due to the use of carbonate ions for ionic transport.
- the present invention relates to the design of such low temperature solid electrolyte fuel cel ls, sensors , or catalysts based on non-oxide sol id electrolytes , such as solid solutions of lanthanide fluorides (e. g .
- the present invention relates to solid materials which have application as an electrolyte for a fuel cell, a sensor or a catalyst. More specifically, the present invention relates to a solid material [AA] for use as an electrolyte for a fuel ceil or for a sensor or as a catalyst, each having a polycrystal or single crystal structure, comprising:
- AF 3 wherein A is independently selected from lanthanum, cerium, neodynium, praseodynium, scandium or mixtures thereof, wherein AF 3 is a single crystal or a portion thereof;
- B is independently selected from strontium, calcium, barium or magnesium, and y is between about 0.0001 and 1; (e) a structure of the formula: A y B 1-y-z LiF 2+y+z wherein A, B and y are as defined hereinabove, z is between about 0.0001 and 0.10 wherein y+z is less than or equal to 1;
- N is independently selected from calcium, strontium or barium, n is between about 0.0001 and 0.05, and m is between about 0.0001 and 0.35;
- PbSnF 4 with the proviso that PbSnF 4 is only useful as a fuel cell electrolyte
- the present invention relates to a process for the preparation of an electrolyte for a fuel cell or for a sensor, which process comprises:
- the present invention relates to a process for the preparation of an electrolyte for a fuel cell or for a sensor, which process comprises:
- a 1-y B y QO 3 having a perovskite or a perovskite-type structure as an electrode catalyst in combination with:
- a y B 1-y F 2+y as a discontinuous surface coating solid electrolyte wherein A is independently selected from lanthanum, cerium, neodymium, praseodymium, or scandium, B is independently selected from strontium, calcium, barium or magnesium, Q is independently selected from nickel, cobalt, iron or manganese, and y is between about 0.0001 and 1, which process comprises:
- a 1-y B y QO 3 wherein A, B and y are defined hereinabove having an average crystal size distribution of between about 50 and 200 Angstroms in diameter and a surface area of between about 10 and 100 meters 2 /grams and formed into a film-like or pellet-like shape having a general thickness of between about 1 and 5mm, a pore size of between about 25 and 200 Anstroms; and (b) reacting the particlulate of step (a) with a vapor comprising:
- a y B 1-x F 2+y wherein A, B and y are defined hereinabove, at about ambient pressure at between about 0 and 1000°C: for between about 10 and 30 hr. obtain the composite of between about 25 to 1000 microns in thickness;
- step (c) recovering the composite of step (b) having multiple interfaces between:
- a preferred embodiment in this process [BB] is wherein A is lanthanum, B strontium, Q is cobalt, and especially where y is about 0.3.
- Another preferred embodiment of process [BB] is wherein A is selected from cerium or scandium, B is selected from strontium or magnesium, Q is selected from nickel, cobalt or manganese and y is between about 0.2-and 0.4.
- the present invention relates to the use of the composite of Claim 16 selected from electrode/electrolyte for a fuel cell, a sensor, or a contact catalyst for synthesis or degradation.
- the present invention relates to the process for the generation of electricity, which process comprises:
- the present invention relates to the process described herein wherein the fuel for the fuel cell is selected from hydrogen, hydrazine, ammonia, fossil fuels, separate components of fossil fuels, or mixtures thereof, wherein all fuels have a boiling point at ambient temperature of 250°C or less. It is especially useful to obtain a fuel cell having an operating temperature between about 10 and 30°C.
- the composite material may be prepared by replacing the perovskite-type structure of the process [BB] with a metal-phthalocyanine structure, wherein the metal is selected from iron, cobalt, nickel and the like.
- the perovskite-type electrode (or the metal-phthalocyanine electrode) and the discontinuous fluoride electrolyte of process [BB] are each thin films of between about 1 and 25 microns on a conventional inorganic catalyst support.
- Figure 1 shows Table 1 as a comparison of various types of fuel cells.
- Figure 2 shows the open circuit voltage (V oc ) versus time using a single crystal of lanthanum fluoride (LaF 3 ).
- Figure 3 shows a configuration of a fuel cell using, for instance, a single crystal of thinly-machined and polished lanthanium fluoride.
- Figure 4 shows a curve of the open circuit voltage versus time using a single crystal of lanthanum fluoride (LaF 3 ).
- Figure 4 is at 0.575 volts using Pd/Pt electrodes.
- Figure 5 is a table showing the open circuit voltage (V oc ) for air, nitrogen, oxygen and hydrogen.
- Figure 6 is a cross section of a solid material composite for solid electrode/electrolyte having a Pt contact, a solid coating of an electrode (e.g. La 0.7 Sr 0.3 F 2.7 with a perovskite-type electrode (e.g.
- Figure 6A is an enlarged cross section showing the discontinuous nature of the electrolyte on a pore opening of the porous electrode.
- Figure 7 is a cross section of a solid material composite useful as a solid electrode having a catalyst support, a platinum contact, a solid coating of an electrolyte (e.g., La. 7 Sr 0.3 F 2.7 ) with a solid discontinuous coating of a perovskite-type (e.g., La 0.7 Sr 0.3 CoO 3 ) or a metal phthalocyanine (Co,Ni, or Fe phthalocyanine) electrode.
- an electrolyte e.g., La. 7 Sr 0.3 F 2.7
- a perovskite-type e.g., La 0.7 Sr 0.3 CoO 3
- a metal phthalocyanine Co,Ni, or Fe phthalocyanine
- Figure 7A is an enlarged cross section showing the discontinuous nature of the electrolyte in contact with the electrode on the solid support.
- lanthanum fluoride is the solid electrolyte of choice for a fuel cell, or a sensor. Its properties are shown below in Table 2.
- -The effective Debye temperature is: +360°K
- -The activation energy for fluorine ion diffusion is ⁇ 0.45 eV
- -Activation energy for the formation of defects ⁇ 0.07eV
- -Thermal expansion coefficient 11x10 -6 cm/cm/°C (c-axis,
- LaF 3 has unique physicochemical properties such as high electrical conductivity and high polarizabifity at room temperature.
- the Debye temperature of LaF 3 is only 360°K , while its melting point is as high as 1766°K .
- the observed phenomena appear to be associated with the formation of Schottky defects and with the diffusion of defects has the unusual ly low value of ⁇ 0.07 eV, and the room temperature Schottky defect density is about 10 19 /cm 3 .
- Fluorine in LaF 3 usually exists in three magnetically nomequivalent sites . Covalent bonding predominates in two of the sites . In the third site, the fluorines make up a layered array with approximately 60% ionic bonding and about 40% ⁇ -bonding .
- the high polarizability and high conductivity of La F 3 at room temperature is primarily due to the motion of F- tons through the latter sites.
- the relatively small radius of F- is almost identical with that of the oxide O 2- ion (1 .25 A) ; therefore oxide ions (O 2- ions) can substitute for the F- ions in LaF 3 . It has been confirmed the oxygen ion transport through the bulk of a single crystal LaF 3 by Auger electron spectroscopy .
- the solid electrolyte LaF 3 serves as a supporting electrolyte analogous to liquid phase in which oxygen ions can move freely .
- LaF 3 has been extensively used as a F- ion selective electrode in eiectroanalyt ⁇ cal chemistry. Recently LaF 3 has been applied to a room temperature potentiometric oxygen sensor and to a multifunctional sensor for humidity, temperature, oxygen gas , and dissolved oxygen .
- polycrystalline lanthanum fluoride as a thin film solid electrode was unreliable and unpredictable. About one of ten electrodes prepared shorted out under laboratory conditions. As is described below, the single crystal lanthanum fluoride solid electrolyte was reliable and predictable.
- FIG 2 illustrates a result on a LaF 3 fuel cell.
- a single crystal of between about 10 and 100 mils is used.
- one cm diameter single crystal LaF 3 with a thickness of 25 mils was used.
- a comb-shape noble metal (Pt, Au, or Pd) electrode (21 + 21 A) was sputtered on both sides of the LaF 3 sample 22.
- One electrode was exposed to pure hydrogen and the other was exposed to room air.
- a Pt/Pt system exhibited an open circuit potential (V oc ) of about 0.6 volts at room temperature. The result was repeatable upon on an on /off cycle of hydrogen.
- V oc When the Pt/oxygen cathode 21 was replaced by a Pd electrode with a different configuration, V oc was increased to 0.88 volts. However, in either case, the observed short circuit currents were in the order of 10 -8 Amperes. This small amount of current is due to the fact that, in the electrode configuration used in our experiments, the total area of the triple-interface (i.e. gas, electrode catalyst, and solid electrolyte) available for electrochemical reactions was extremely small. Current density is greatly increased when a large surface area platinum black is used as an electrode. The following electrochemical reactions may take place at each electrode:
- V oc RT/4F I n (At electrode #1 ) / P (At electrode #2) where stands for partial pressure of oxygen at the electrode specified , R is the universal gas constant, T is the temperature in Kelvin , and
- each of the structures (a) through (m ) are each independently preferred as a solid electrolyte for a fuel cell , a sol id electrolyte for a sensor or as a catalyst, espeacially as fuel cell or a sensor.
- the solid material material [AA] of the SUMMARY is selected from structures of formula (a), (b), (d), (e) or (j).
- the solid material of [AA] of the SUMMARY is selected from structures of formula (a), (b), (f), (h), (j) or (k).
- fuel cell of material [AA] above has a useful operational temperature range of between about 0 and 1000°C especially wherein the structure in subpart (a) is AF 3 wherein A is lanthanum, and also where the operational temperature is between about 15 and 30°C; [2]. the electrolyte of material [AA] is used in a device as a sensor to detect gases selected from oxygen in the gaseous phase or dissolved in a liquid; [3] the electrolyte of material [AA] is used for a sensor wherein the sensor has a useful operating range of between about -40°C to + 1000°C; or
- the solid material [AA] above as an electrolyte for a sensor of [AA] above is wherein the oxygen sensor has an operating range of between about 0°C and 600°C.
- the solid materials of [AA] are unless otherwise stipulated, individually preferred as a component of a fuel cell, of a sensor or as a catalyst useful in the interconversion formation and degradation of organic compounds, nitrogen-containing compounds and the like.
- solid materials described herein for use as solid electrolytes for fuel and for sensors optionally include pretreatment of the surface of the solid , preferably structures of formula (a) , especially where A is lanthanum as described herein below .
- the materials described in the Summary of the Invention (and in Claim 1 ) are sintered in an oxygen environment at elevated temperature.
- the material is placed in an oxygen atmosphere containing from 1 to 99 percent by weight of water.
- the water present is between about 10 and 30 percent by weight especially about 15 percent by weight.
- the temperature is usually between about 100 and 1000°C , preferably between about 150 and 600°C, especially between about 200 and 400°C.
- the electrochemical doping (pumping ) of oxide ions is achieved by subjecting about 1 gram the material [AA] to 10 -3 amperes per square centimeter for between about 1 to 25 hr at ambient temperature. Stated in another way about 1 gram of the structure of the material [AA] above is subjected to a certain amount of coulombs equivalent to a product of one Faraday (coulombs/mole) times X where X is between about 0.001 and 1 a depending on the specific material [AA] structure (a) to (m). This electrochemical pumping may be performed between about 0 and 400°C.
- the electrocatalysts for the above cited low temperature solid electrolyte fuel cell can be noble metals (e.g. platinum), their alloys or blacks, metal-phthalocyanines, transition metal catalysts (e.g. Ni/NiO), and metallic transition metal oxides (e.g.
- a 1-x BxQO 3 where A, B, Q and x are as defined hereinabove as catalytic electrode materials, especially for the oxygen reaction in conjunction with the lanthanide fluoride solid electrolyte:
- a x B 1-x F 2+x wherein A is: (La, Ce, Nd, Pr or Sc); and B is: (Sr, Ca, Ba or Mg); and x is between about 0.001 and 1.
- Electrode La 0.7 Sr 0.3 F 2.7
- electrode Electrode: La 0.7 Sr 0.3 F 2.7
- a 1-x B x QO 3 /A x B 1-x F 2+x can be an ideal site to facilitate the following reaction:
- perovskites useful in this invention may be purchased or may fe formed according to the procedures described in the literature e.g., T. Kudo et al., U.S. Patent No. 3,804,674, which is incorporated herein by reference.
- FIG 6 shows the configuration of a composite for use in a fuel cell.
- the perovskite. substrate (porous oxide) electrode 61 is treated with a vapor to deposit the fluoride electrolyte 62 on the surface.
- fluoride 62 or 65 will enter the pores of the perovskite and also be on the surface 64 of the perovskite in a discontinuous manner. In this way, millions of two material catalytic surfaces sites 66 are created to facilitate the electrochemical reaction at the intersection of the perovskite 61 and fluoride (62 or 65).
- Figure 7 shows the configuration of a supported composite for use in a fuel cell.
- the perovskite substrate 71 is spray dried onto an inorganic support 70 such as silica, thoria, zirconia, magnesia, or the like having mechanical stability.
- the fluoride electrolyte 72 is then vapor deposited on the surface of the perovskite 71.
- the fluoride electrolyte 72 as a vapor enters the pores of the perovskite 71 and the substrate 70 in a discontinuous manner. In this way, millions of two-material catalytic surfaces 74 are created to facilitate the electrochemical reaction at the intersection of the perovskite 71 and fluoride 72.
- Metal Phthalocyanines Metal Phthalocyanines
- the present invention also contemplates the use of metal-phthalocyanines in electrode/electrolyte composites.
- the metal-phthalocyanine in this embodiment of the invention, the metal-phthalocyanine
- Z-phthalocyanine is used to replace the perovskite-type oxide described above on a weight to weight basis and is then combined with the solid electrolyte as is described above.
- the metal ions (Z-) preferred include iron, cobalt, nickel and the like.
- Typical metal-phthalocyanines in these composites include those described above and, for example, those and similar ones described by K.V. Kordesch in U.S. Patent No. 3,783,026, which is incorporated herein by reference.
- the composites described below in Claims 28, 29, 30 or 31 are preferred.
- sensors in analiytical devices to determine components in the vapor phase and also in the liquid phase. These sensors are preferably useful to analyze oxygen, carbon dioxide , methane, ethane, ethylene, ammonia , hydrogen suifide or the like. Lanthanum fluoride is preferred to analyze oxygen in a gaseous phase or in a liquid , preferably an aqueous solution.
- the range of the analysis may be from between about a part per billion to 10 ,000 parts per million in the gas phase (usually performed in the potentiometric mode) . Even high concentrations of a component, for instance, in the liquid phase determined in the current mode because the proportionality is linear rather than logrithmic.
- the solid material for use as an electrolyte in a fuel cell or in a sensor or for use as catalyst is selected from structures of (b) , (c) , (d) , (e) , (f) , (h) , (i) , (j) , (k) , (I) , or (m) .
- a more preferred embodiment of the solid material is selected from the structures of (b) , (c) , (d) , or (e) .
- Another preferred embodiment of the solid material is selected from the structures of (k) , (I ) or (m) .
- EXAMPLE 1 Formation of Solid Thin Films and Fuel Cell Measurements (aa) As is described in B.C. LaRoy et al., (above, and incorporated herein by reference), lead .75 potassium .25 fluoride 1 .75 (Pb 0.75 K 0 .25 F 1 .75 ) is evaporated onto in a thin polycrystalline film onto a substrate to a thickness of 25 mils. Pt black is coated onto the polycrystalline film. One electrode is exposed to pure hydrogen and the other is exposed to room air. This Pt/solid electrode/ Pt system is expected to exhibit a useful open circuit, potential (V oc ) of between about 0.5 and 1.0 volts.
- V oc useful open circuit, potential
- the fuel cell obtained is expected to generate a useful open circuit potential (V oc ) of between about 0.5 and 1.0 volts.
- a pure lanthanum nickelate crystal is synthesized by a co-precipitation technique.
- the starting materials are La(NO 3 ) 3 ⁇ 6H 2 O and Ni(NO 3 ) 2 ⁇ 6H 2 O (alternatively acetates and chlorides can be used as the starting materials).
- the proper amounts of each nitrate required to give the desired stoichiometry are weighed and dissolved in doubly distilled water to remove Na + and separated quickly by a centrifuge technique at 2000 rpm for 15 min., since Ni(OH) 2 tends to dissolve at pH ⁇ 7. This process is repeated several times.
- the obtained precipitates are dried in an oven at 100°C overnight.
- the dried powder is then put in the furnace at 800°C for 16 hours in an O 2 atmosphere.
- the electrode is made by pressing the powders into
- a thin film (about 100 micrometers) of La 0.5 Sr 0.5 F 2.5 is prepared on the perovskite layer by conventional vacuum evaporation (LeRoy et al.) using pure materials of lanthanum fluoride and strontium fluoride in a tungsten boat applying a current of about 40 amperes in a high vacuum of about 10 torr.
- the composite obtained is expected to have a useful open circuit potential of between about 0.5 and 1.0 volts.
- a thin layer of a perovskite oxide is prepared on a porous substrate (e.g. alumina, zirconia oxide with pore size of abut 100 A with a thickness 1-2 mm) by a spray pyrolysis.
- a porous substrate e.g. alumina, zirconia oxide with pore size of abut 100 A with a thickness 1-2 mm
- the 50% Sr doped LaCoO 3 is prepared as follows: 8.5g Sr(NO 3 ) 2 , 23.3g Co(NO 3 ) 2 ⁇ 6H 2 O and 17.81g La(NO 3 ) 3 ⁇ 6H 2 O (alternatively acetates and chlorides can be used as the starting materials) are dissolved in disltilled water and sprayed onto the hot porous substrate (about 10 cm by 10 cm) at a flow rate of about 10 mL/min. The homogeneous constituent is then decomposed at 250°C, fol lowed by quenching oxygen and heating 500° C, in air for 3hr.
- the perovskite catalyst loading should be about 10mg/cm 2 .
- a thin film (about 100 ⁇ m) of La 0 .5 Sr 0 .5 F 2 .5 is prepared on the perovskite layer by a vacuum evaporation using pure materials of LaF 3 and SrF 2 in a tungsten boat and applying a current of about 40 Amperes in high vacuum of about 10 torr.
- pure metal targets can be used in a sputtering process in a low pressure fluorine atmosphere (e.g . 10 m torr) .
- the obtained fuel cel l is expected to generate an open circuit potential (V oc ) of between about 0.5 and 1 .0 volts . (See Figure 6 , 6A, 7 , 7A) .
- EXAMPLE 4 FORMATI ON OF A S I NGLE CRYSTAL BASED FUEL CELL A single crystal of lanthanum fluoride is pretreated in an oxygen atmosphere of 50% oxygen. The single crystal is cut into slabs and one slab is polished down to a thickness of 100-200 micrometers. A layer of porous platinum black of between 100 and 200 micrometers thickness is coated on opposite faces of the slab . One electrode is exposed to pure hydrogen and the other electrode is exposed to room air . This platinum/sol id lanthanum fluoride electrolyte/platinum is expected to exhibit a useful open circuit potential (V oc ) of between about 0.5 and 1 .0 volts . EXAMPLE 5 LaF 3 as a Sensor for Oxygen
- Solid materials for use as electrolyte (62) for a fuel cell, or for a sensor, or as a catalyst include lanthanum fluoride, lead potassium fluoride, lead bismuth fluoride, lanthanum strontium fluoride, lanthan strontium lithium fluoride, calcium uranium cesium fluoride, PbSnF 4 , KSn 2 F 5 , SrCl 2 .KCl, La,.
- the present invention relates to a composite and a process to obtain it of the formula: A ⁇ -y B y Q0 3 having a perovskite or a perPEROVSKITE: eg.
- the invention relates to the heating these solid materials with oxygen and water to obtain higher ionic conductivity.
- the invention relates the electrochemical doping of oxide ions present by treatment of the electrode-lanthanum fluoride interface at betwe about 0 and 400°C in an oxygen environment at between about 10- 3 and l(r 6 amperes per square centimeter for betwe about 1 and 60 minutes.
- the invention also includes the use of the fuel cells disclosed to generate electricity.
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8814497A GB2208750B (en) | 1986-11-26 | 1987-11-02 | Solid electrolyte fuel cells |
DE873790732T DE3790732T1 (en) | 1986-11-26 | 1987-11-02 | SOLID FOR USE AS AN ELECTROLYTE FOR A FUEL CELL OR MEASURING PROBE OR AS A CATALYST |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US935,289 | 1986-11-26 | ||
US06/935,289 US4851303A (en) | 1986-11-26 | 1986-11-26 | Solid compositions for fuel cells, sensors and catalysts |
Publications (2)
Publication Number | Publication Date |
---|---|
WO1988004108A2 true WO1988004108A2 (en) | 1988-06-02 |
WO1988004108A3 WO1988004108A3 (en) | 1988-08-25 |
Family
ID=25466871
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1987/002881 WO1988004108A2 (en) | 1986-11-26 | 1987-11-02 | Solid compositions for fuel cells, sensors and catalysts |
Country Status (5)
Country | Link |
---|---|
US (2) | US4851303A (en) |
EP (1) | EP0291528A1 (en) |
JP (1) | JPH01501510A (en) |
GB (1) | GB2208750B (en) |
WO (1) | WO1988004108A2 (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1989011739A2 (en) * | 1988-05-20 | 1989-11-30 | Sri International | Solid compositions for fuel cell electrolytes |
FR2650918A1 (en) * | 1989-08-09 | 1991-02-15 | Tsnt Tv | SOLID ELECTROLYTE AND PROCESS FOR OBTAINING THE SAME |
EP0414270A2 (en) * | 1989-08-24 | 1991-02-27 | Kabushiki Kaisha Meidensha | Fuel cell utilizing solidous electrolyte |
WO1995032799A1 (en) * | 1994-05-26 | 1995-12-07 | E.I. Du Pont De Nemours And Company | Catalysts for halogenated hydrocarbon processing, their precursors and their preparation and use |
US5847242A (en) * | 1995-05-19 | 1998-12-08 | E. I. Du Pont De Nemours And Company | Catalysts for halogenated hydrocarbon processing, their precursors and their preparation and use |
WO1999008327A1 (en) * | 1997-08-06 | 1999-02-18 | Forschungszentrum Jülich GmbH | Component with rectifying function, fulfilled by means of charge transport by ions |
Families Citing this family (57)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5134042A (en) * | 1986-11-26 | 1992-07-28 | Sri International | Solid compositions for fuel cells, sensors and catalysts |
US5274070A (en) * | 1988-07-22 | 1993-12-28 | Osaka Gas Company, Ltd. | Iron-Schiff base magnetic polymers and process thereof |
US5001021A (en) * | 1989-12-14 | 1991-03-19 | International Fuel Cells Corporation | Ceria electrolyte composition |
US5223471A (en) * | 1990-12-12 | 1993-06-29 | Amoco Corporation | Fluorine-containing materials |
JPH04238815A (en) * | 1991-01-14 | 1992-08-26 | Matsushita Electric Ind Co Ltd | Fluoride ion conductor and electrochemical element using the same |
US5322611A (en) * | 1991-01-31 | 1994-06-21 | Solomon Zaromb | Humidity-resistant ambient-temperature solid-electrolyte amperometric sensing apparatus |
JP2882104B2 (en) * | 1991-07-17 | 1999-04-12 | 松下電器産業株式会社 | Proton conductor and method for producing the same |
US5256272A (en) * | 1992-03-10 | 1993-10-26 | Alcock Charles B | Electrochemical sensor for determining the level of a certain metal in metals and alloys |
US5624542A (en) * | 1992-05-11 | 1997-04-29 | Gas Research Institute | Enhancement of mechanical properties of ceramic membranes and solid electrolytes |
US5356728A (en) * | 1993-04-16 | 1994-10-18 | Amoco Corporation | Cross-flow electrochemical reactor cells, cross-flow reactors, and use of cross-flow reactors for oxidation reactions |
US5610324A (en) * | 1993-11-08 | 1997-03-11 | Fugitive Emissions Detection Devices, Inc. | Fugitive emissions indicating device |
GB9408542D0 (en) * | 1994-04-29 | 1994-06-22 | Capteur Sensors & Analysers | Gas sensing resistors |
US5846669A (en) * | 1994-05-12 | 1998-12-08 | Illinois Institute Of Technology | Hybrid electrolyte system |
AU706663B2 (en) * | 1994-09-23 | 1999-06-17 | Standard Oil Company, The | Oxygen permeable mixed conductor membranes |
US5607784A (en) * | 1995-01-19 | 1997-03-04 | Electrochem, Inc. | Hydrogen/fluorine power generating system |
US5543239A (en) * | 1995-04-19 | 1996-08-06 | Electric Power Research Institute | Electrode design for solid state devices, fuel cells and sensors |
US5518830A (en) * | 1995-05-12 | 1996-05-21 | The Trustees Of The University Of Pennsylvania | Single-component solid oxide bodies |
CA2182069C (en) | 1995-08-24 | 2002-04-09 | Victor P. Crome | Modular ceramic oxygen generator |
US5985113A (en) * | 1995-08-24 | 1999-11-16 | Litton Systems, Inc. | Modular ceramic electrochemical apparatus and method of manufacture therefor |
KR0165651B1 (en) * | 1995-09-28 | 1999-03-30 | 모리시타 요이치 | Electrochemical device |
US6117582A (en) * | 1995-11-16 | 2000-09-12 | The Dow Chemical Company | Cathode composition for solid oxide fuel cell |
US5670270A (en) * | 1995-11-16 | 1997-09-23 | The Dow Chemical Company | Electrode structure for solid state electrochemical devices |
US5993986A (en) * | 1995-11-16 | 1999-11-30 | The Dow Chemical Company | Solide oxide fuel cell stack with composite electrodes and method for making |
WO1997026684A1 (en) * | 1996-01-18 | 1997-07-24 | The Arizona Board Of Regents On Behalf Of The University Of Arizona | Single-crystal oxygen ion conductor |
US5759936A (en) * | 1996-03-21 | 1998-06-02 | Haldor Topsoe As | Lanthanide ceramic material |
US6228520B1 (en) | 1997-04-10 | 2001-05-08 | The Dow Chemical Company | Consinterable ceramic interconnect for solid oxide fuel cells |
US5935727A (en) * | 1997-04-10 | 1999-08-10 | The Dow Chemical Company | Solid oxide fuel cells |
US5922486A (en) * | 1997-05-29 | 1999-07-13 | The Dow Chemical Company | Cosintering of multilayer stacks of solid oxide fuel cells |
USRE39556E1 (en) * | 1997-11-20 | 2007-04-10 | Relion, Inc. | Fuel cell and method for controlling same |
US6096449A (en) * | 1997-11-20 | 2000-08-01 | Avista Labs | Fuel cell and method for controlling same |
US6030718A (en) * | 1997-11-20 | 2000-02-29 | Avista Corporation | Proton exchange membrane fuel cell power system |
US6228521B1 (en) | 1998-12-08 | 2001-05-08 | The University Of Utah Research Foundation | High power density solid oxide fuel cell having a graded anode |
US6638654B2 (en) * | 1999-02-01 | 2003-10-28 | The Regents Of The University Of California | MEMS-based thin-film fuel cells |
MXPA01010639A (en) | 1999-04-20 | 2003-08-20 | Zinc Air Power Corp | Lanthanum nickel compound/metal mixture as a third electrode in a metal-air battery. |
US6235417B1 (en) | 1999-04-30 | 2001-05-22 | Her Majesty The Queen In Right Of Canada, As Represented By The Minister Of Natural Resources | Two-phase hydrogen permeation membrane |
US7326480B2 (en) * | 2000-05-17 | 2008-02-05 | Relion, Inc. | Fuel cell power system and method of controlling a fuel cell power system |
US6468682B1 (en) | 2000-05-17 | 2002-10-22 | Avista Laboratories, Inc. | Ion exchange membrane fuel cell |
US6632554B2 (en) | 2001-04-10 | 2003-10-14 | Hybrid Power Generation Systems, Llc | High performance cathodes for solid oxide fuel cells |
US6905386B2 (en) * | 2002-03-15 | 2005-06-14 | Arko Development Limited | Apparatus and method for delivering bubble solution to a dipping container |
US7045231B2 (en) * | 2002-05-22 | 2006-05-16 | Protonetics International, Inc. | Direct hydrocarbon reforming in protonic ceramic fuel cells by electrolyte steam permeation |
CA2487859A1 (en) * | 2002-05-29 | 2004-05-13 | The Board Of Trustees Of The Leland Stanford Junior Unversity | Solid oxide electrolyte with ion conductivity enhancement by dislocation |
WO2004033061A2 (en) * | 2002-10-04 | 2004-04-22 | The Regents Of The University Of California | Fluorine separation and generation device |
US7332237B2 (en) * | 2003-01-27 | 2008-02-19 | Protonetics International, Inc. | Stream reforming of solid carbon in protonic ceramic fuel cells |
JP4574149B2 (en) * | 2003-09-17 | 2010-11-04 | 株式会社豊田中央研究所 | Electrolyte membrane electrode assembly for polymer electrolyte fuel cell and polymer electrolyte fuel cell |
US7476461B2 (en) * | 2003-12-02 | 2009-01-13 | Nanodynamics Energy, Inc. | Methods for the electrochemical optimization of solid oxide fuel cell electrodes |
US20050135993A1 (en) * | 2003-12-23 | 2005-06-23 | Jun Xu | Manganese oxide based materials as ion intercalation hosts in lithium batteries |
US7208437B2 (en) * | 2004-01-16 | 2007-04-24 | T/J Technologies, Inc. | Catalyst and method for its manufacture |
US7255949B2 (en) | 2004-05-25 | 2007-08-14 | Protonetics International, Inc. | Systems and methods to generate hydrogen and electrical power in a reversible compound fuel cell |
US7691523B2 (en) * | 2007-10-31 | 2010-04-06 | Samsung Electronics Co., Ltd. | Method of preparing fuel cell comprising proton conducting solid perovskite electrolyte membrane with improved low temperature ion conductivity, and membrane electrode assembly of fuel cell prepared by the method |
JP5120075B2 (en) * | 2008-06-03 | 2013-01-16 | トヨタ自動車株式会社 | Fuel cell system |
US20120251922A1 (en) | 2011-03-28 | 2012-10-04 | WATT Fuel Cell Corp | Electrode for a solid oxide fuel cell and method for its manufacture |
US9642192B2 (en) * | 2011-08-04 | 2017-05-02 | Fuelcell Energy, Inc. | Method and manufacturing assembly for sintering fuel cell electrodes and impregnating porous electrodes with electrolyte powders by induction heating for mass production |
JP6455917B2 (en) * | 2013-10-04 | 2019-01-23 | 国立研究開発法人産業技術総合研究所 | Catalyst for electrochemical reduction of oxygen |
JP6638622B2 (en) * | 2016-11-08 | 2020-01-29 | トヨタ自動車株式会社 | Fluoride ion battery and method of manufacturing the same |
JP6536538B2 (en) * | 2016-11-08 | 2019-07-03 | トヨタ自動車株式会社 | Fluoride ion battery and method of manufacturing the same |
JP7040903B2 (en) | 2017-07-03 | 2022-03-23 | パナソニック株式会社 | Fluoride Ion Conductive Materials and Fluoride Shuttle Rechargeable Batteries |
US20200249190A1 (en) * | 2019-01-31 | 2020-08-06 | The Board Of Trustees Of The University Of Alabama | Portable impedance based chemical sensor |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1442686A1 (en) * | 1963-10-23 | 1969-04-24 | Bayer Ag | Mixed phases of fluorite or fluorite-like structure and predominantly oxidic compounds as host lattices |
FR2330127A1 (en) * | 1975-10-30 | 1977-05-27 | Anvar | Anionic fluoride conductors comprising solid solns. - for use as solid electrolytes in batteries |
GB2002739A (en) * | 1977-08-10 | 1979-02-28 | Dornier System Gmbh | Connecting material for electrical connection of electrochemical cells |
FR2403652A2 (en) * | 1977-09-16 | 1979-04-13 | Anvar | Anion deficient fluoride thin films - used in prodn. of galvanic cells and formed by vapour deposition on substrates in microelectronics |
DE3112739A1 (en) * | 1981-03-31 | 1982-10-07 | Bosch Gmbh Robert | Electrode of stable structure for solid-state electrolytes for electrochemical applications, and use of such an electrode in electrochemical sensors for determining the oxygen content in gases |
US4402924A (en) * | 1978-01-16 | 1983-09-06 | Exxon Research And Engineering Co. | Preparation of high surface area metal fluorides and metal oxyfluorides, especially aluminum fluoride extrudates |
EP0194380A2 (en) * | 1985-03-15 | 1986-09-17 | Westinghouse Electric Corporation | Support tubes for electrochemical cells |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1070937A (en) * | 1963-05-08 | 1967-06-07 | Comp Generale Electricite | Electrical fuel cells |
US3698955A (en) * | 1969-11-20 | 1972-10-17 | Philip Morris Inc | Oxygen-responsive electrical current supply |
CH594292A5 (en) * | 1974-11-19 | 1978-01-13 | Raffinage Cie Francaise | |
US4352869A (en) * | 1980-12-24 | 1982-10-05 | Union Carbide Corporation | Solid state electrolytes |
US4598467A (en) * | 1984-10-05 | 1986-07-08 | Westinghouse Electric Corp. | Protective interlayer for high temperature solid electrolyte electrochemical cells |
JPS61132855A (en) * | 1984-11-30 | 1986-06-20 | Shimadzu Corp | Oxygen sensor |
-
1986
- 1986-11-26 US US06/935,289 patent/US4851303A/en not_active Expired - Fee Related
-
1987
- 1987-11-02 EP EP88900406A patent/EP0291528A1/en not_active Withdrawn
- 1987-11-02 JP JP63500646A patent/JPH01501510A/en active Pending
- 1987-11-02 GB GB8814497A patent/GB2208750B/en not_active Expired - Lifetime
- 1987-11-02 WO PCT/US1987/002881 patent/WO1988004108A2/en not_active Application Discontinuation
-
1988
- 1988-05-20 US US07/196,498 patent/US4948680A/en not_active Expired - Fee Related
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1442686A1 (en) * | 1963-10-23 | 1969-04-24 | Bayer Ag | Mixed phases of fluorite or fluorite-like structure and predominantly oxidic compounds as host lattices |
FR2330127A1 (en) * | 1975-10-30 | 1977-05-27 | Anvar | Anionic fluoride conductors comprising solid solns. - for use as solid electrolytes in batteries |
GB2002739A (en) * | 1977-08-10 | 1979-02-28 | Dornier System Gmbh | Connecting material for electrical connection of electrochemical cells |
FR2403652A2 (en) * | 1977-09-16 | 1979-04-13 | Anvar | Anion deficient fluoride thin films - used in prodn. of galvanic cells and formed by vapour deposition on substrates in microelectronics |
US4402924A (en) * | 1978-01-16 | 1983-09-06 | Exxon Research And Engineering Co. | Preparation of high surface area metal fluorides and metal oxyfluorides, especially aluminum fluoride extrudates |
DE3112739A1 (en) * | 1981-03-31 | 1982-10-07 | Bosch Gmbh Robert | Electrode of stable structure for solid-state electrolytes for electrochemical applications, and use of such an electrode in electrochemical sensors for determining the oxygen content in gases |
EP0194380A2 (en) * | 1985-03-15 | 1986-09-17 | Westinghouse Electric Corporation | Support tubes for electrochemical cells |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1989011739A2 (en) * | 1988-05-20 | 1989-11-30 | Sri International | Solid compositions for fuel cell electrolytes |
WO1989011739A3 (en) * | 1988-05-20 | 1990-04-05 | Stanford Res Inst Int | Solid compositions for fuel cell electrolytes |
FR2650918A1 (en) * | 1989-08-09 | 1991-02-15 | Tsnt Tv | SOLID ELECTROLYTE AND PROCESS FOR OBTAINING THE SAME |
GB2235537A (en) * | 1989-08-09 | 1991-03-06 | Tsnt Tvorchestva Molodezhi Gal | Solid electrolyte for electrochemical cells and process for making same |
EP0414270A2 (en) * | 1989-08-24 | 1991-02-27 | Kabushiki Kaisha Meidensha | Fuel cell utilizing solidous electrolyte |
EP0414270A3 (en) * | 1989-08-24 | 1991-11-13 | Kabushiki Kaisha Meidensha | Fuel cell utilizing solidous electrolyte |
US5151334A (en) * | 1989-08-24 | 1992-09-29 | Kabushiki Kaisha Meidensha | Fuel cell utilizing solidous electrolyte |
WO1995032799A1 (en) * | 1994-05-26 | 1995-12-07 | E.I. Du Pont De Nemours And Company | Catalysts for halogenated hydrocarbon processing, their precursors and their preparation and use |
US5559069A (en) * | 1994-05-26 | 1996-09-24 | E. I. Du Pont De Nemours And Company | Catalysts for halogenated hydrocarbon processing, their precursors and their preparation and use |
US5847242A (en) * | 1995-05-19 | 1998-12-08 | E. I. Du Pont De Nemours And Company | Catalysts for halogenated hydrocarbon processing, their precursors and their preparation and use |
WO1999008327A1 (en) * | 1997-08-06 | 1999-02-18 | Forschungszentrum Jülich GmbH | Component with rectifying function, fulfilled by means of charge transport by ions |
US6486501B1 (en) | 1997-08-06 | 2002-11-26 | Forschungszentrum Julich Gmbh | Component with rectifying function, fulfilled by means of charge transport by ions |
Also Published As
Publication number | Publication date |
---|---|
GB2208750A (en) | 1989-04-12 |
US4948680A (en) | 1990-08-14 |
JPH01501510A (en) | 1989-05-25 |
US4851303A (en) | 1989-07-25 |
GB8814497D0 (en) | 1988-07-27 |
WO1988004108A3 (en) | 1988-08-25 |
EP0291528A1 (en) | 1988-11-23 |
GB2208750B (en) | 1991-03-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4851303A (en) | Solid compositions for fuel cells, sensors and catalysts | |
US5134042A (en) | Solid compositions for fuel cells, sensors and catalysts | |
Zhang et al. | Advanced materials for thin‐film solid oxide fuel cells: recent progress and challenges in boosting the device performance at low temperatures | |
Hibino et al. | A solid oxide fuel cell using Y-doped BaCeO3 with Pd-loaded FeO anode and Ba0. 5Pr0. 5CoO3 cathode at low temperatures | |
Xing et al. | Co-electrolysis of steam and CO2 in a solid oxide electrolysis cell with La0. 75Sr0. 25Cr0. 5Mn0. 5O3− δ–Cu ceramic composite electrode | |
Mutoro et al. | Reversible compositional control of oxide surfaces by electrochemical potentials | |
Hrovat et al. | Characterisation of LaNi1− xCoxO3 as a possible SOFC cathode material | |
Fabbri et al. | Composite cathodes for proton conducting electrolytes | |
Primdahl et al. | Sr-doped LaCrO3 anode for solid oxide fuel cells | |
US6746791B2 (en) | Nano-ionic products and devices | |
KR100352099B1 (en) | Mixed ions containing conductor and device using the same | |
Alcock et al. | Perovskite electrodes for sensors | |
US5273628A (en) | Mixed ionic-electronic conductors for oxygen separation and electrocatalysis | |
Decorse et al. | A comparative study of the surface and bulk properties of lanthanum-strontium-manganese oxides La1− xSrxMnO3±δ as a function of Sr-content, oxygen potential and temperature | |
JP4608047B2 (en) | Mixed ionic conductor and device using the same | |
US6117582A (en) | Cathode composition for solid oxide fuel cell | |
Li et al. | Efficient carbon dioxide electrolysis based on perovskite cathode enhanced with nickel nanocatalyst | |
JPH08247992A (en) | Nitrogen oxide sensor | |
US20100015489A1 (en) | Titanates of Perovskite or Derived Structure and Applications Thereof | |
JP2007197315A (en) | Mixed ion conductor and device using the same | |
Wang et al. | High‐entropy perovskites for energy conversion and storage: design, synthesis, and potential applications | |
US20020187389A1 (en) | Cathode composition for solid oxide fuel cell | |
Nicollet et al. | Perspective on the relationship between the acidity of perovskite oxides and their oxygen surface exchange kinetics | |
Seo et al. | Degradation and recovery of solid oxide fuel cell performance by control of cathode surface acidity: Case study–Impact of Cr followed by Ca infiltration | |
Yoon et al. | Calcium-and cobalt-doped yttrium chromites as an interconnect material for solid oxide fuel cells |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A2 Designated state(s): DE GB JP KR |
|
AL | Designated countries for regional patents |
Kind code of ref document: A2 Designated state(s): FR IT |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1988900406 Country of ref document: EP |
|
AK | Designated states |
Kind code of ref document: A3 Designated state(s): DE GB JP KR |
|
AL | Designated countries for regional patents |
Kind code of ref document: A3 Designated state(s): FR IT |
|
COP | Corrected version of pamphlet |
Free format text: PAGES 1-8 OF THE DRAWINGS REPLACED BY NEW PAGES 1-9 |
|
WWP | Wipo information: published in national office |
Ref document number: 1988900406 Country of ref document: EP |
|
RET | De translation (de og part 6b) |
Ref document number: 3790732 Country of ref document: DE Date of ref document: 19891019 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 3790732 Country of ref document: DE |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 1988900406 Country of ref document: EP |