Gas Research Institute

Ceramatec, Inc.

University of Utah Research Foundation

Materials and Systems Research, Inc.

The Dow Chemical Company

Ford Motor Company Limited

The United States of America As Represented by the United States

Praxair Technology, Inc.

Electric Power Research Institute Incorporated

Materials Research Corporation

Cerametec, Inc.

Anil Vasudeo Virkar

Kuan-Zong Fung

Ashok V Joshi

Jan-Fong Jue

Raymond Ashton Cutler

Yousheng Shen

Kevin Krist

Meilin Liu

Ivan B Cutler

Gerald R Miller

Ronald S Gordon

Jai-Woh Kim

Diane M England

James R Rasmussen

John Howard Gordon

Ravi Prasad

Christian Friedrich Gottzmann

Shekar H Balagopal

Bryan J McEntire

Dale M Taylor

Roger L Matsumoto

Bart Antonie Van Hassel

Ram Natesh

Paul C Smith

Liang Jun Li

Mohammed N Shaikh

Wensheng Wang

Thomas C Yuan

Andrew C Hurford

Karun Mehta

Sanjeevani Vidyadhar Bhide

David W Prouse

Cameron W Tanner

Michael J Boettcher

Guang-Young Lin

Arun D Jatkar

Mark L Miller

A core-shell catalyst material can include a core and a shell material. Each of the core material and the shell material can have crystal structures and lattice parameters which allow for a substantially coherent core-shell interface. The shell material can include a catalytically active metal. The circumferential stress of the shell material, &#x3c3;, at the core-shell interface and at the shell surface, is greater than 0 (tensile) or can be compressive of a lower magnitude than a catalyst made of the shell material alone. The crystal structures of the core material can often be the same as the shell material, although this is not always required.

Core shell catalyst

A method for synthesizing nanosize metallic powders can include providing a metallic precursor. The metallic precursor can include a metal alloy formed having a fugitive constituent and a target metal. The fugitive constituent and target metal are chosen such that the fugitive constituent can be selectively dissolved or removed by leaching with an appropriate solvent while leaving the target metal undissolved. The fugitive constituent can be leached from the metallic precursor to leave a metallic residue which is a mass of nanosize metallic particles made substantially of the target metal. The nanosize metallic particles can then be recovered from the metallic residue either merely by removing the solvent and/or breaking up the mass of nanosize metallic particles. The disclosed methods allow for a convenient avenue for production of nanosize particles from readily formed materials for use in a wide variety of potential industrial and commercial applications.

Molecular decomposition processes for the synthesis of nanosize metallic powders

A process is disclosed for forming a nanosize ceramic powder. A precursor ceramic material is formed of a fugitive constituent and a non-soluble constituent in a single phase. The precursor is contacted with a selective solvent (water, acid, etc.) to form a solution of the fugitive constituent in the solvent and a residue of the non-soluble constituent. The precursor is sufficiently reactive with the solvent to form the solution of the fugitive constituent in the solvent and form the nondissolved residue of the non-soluble constituent. The precursor material and the non-soluble residue are sufficiently insoluble in the solvent such that there is insufficient precursor material and non-soluble residue in solution to deposit and precipitate upon the residue of the non-soluble-constituent. The fugitive constituent is sufficiently soluble in the solvent such that the precursor reacts with the solvent to form the solution of the fugitive constituent without precipitation and deposition of fugitive constituent upon the residue of the non-soluble constituent in the form of nanosize particles. After the fugitive constituent is dissolved the selective solvent containing the fugitive constituent is removed from the residue. The residue remains in the form of a nanosize powder of the non-soluble constituent.

Molecular decomposition process for the synthesis of nanosize ceramic and metallic powders

A metallic interconnect for use in planar solid oxide fuel cell (SOFC) stacks with metal gauzes disposed in border pieces at the cathodes and anodes providing the electrical conduction between the cell and an interconnect foil and also providing structure for directing gas across the cell surface.

Internally manifolded, planar solid oxide fuel cell (SOFC) stack with an inexpensive interconnect

A ceramic composite containing alkali-metal-beta- or beta&Prime;-alumina and an oxygen-ion conductor is fabricated by converting alpha-alumina to alkali-metal-beta- or beta&Prime;-alumina. A ceramic composite with continuous phases of alpha-alumina and the oxygen-ion conducting ceramic, such as zirconia, is exposed to a vapor containing an alkali-metal oxide, such as an oxide of sodium or potassium. Alkali metal ions diffuse through alkali-metal-beta- or beta&Prime;-alumina converted from &agr;-alumina and oxygen ions diffuse through the oxygen-ion conducting ceramic to a reaction front where alpha-alumina is converted to alkali-metal-beta- or beta&Prime;-alumina. A stabilizer for alkali-metal-beta&Prime;-alumina is preferably introduced into the &agr;-alumina/oxygen-ion conductor composite or introduced into the vapor used to convert the alpha-alumina to an alkali-metal-beta&Prime;-alumina.

Alkali-metal-beta-and beta&Prime;-alumina and gallate polycrystalline ceramics and fabrication by a vapor phase method

A ceramic composite containing alkali-metal-&bgr;- or &bgr;&Prime;-alumina and an oxygen-ion conductor is fabricated by converting &agr;-alumina to alkali-metal-&bgr;- or &bgr;&Prime;-alumina. A ceramic composite with continuous phases of &agr;-alumina and the oxygen-ion conducting ceramic, such as zirconia, is exposed to a vapor containing an alkali-metal oxide, such as an oxide of sodium or potassium. Alkali metal ions diffuse through alkali-metal-&bgr;- or &bgr;&Prime;-alumina converted from &agr;-alumina and oxygen ions diffuse through the oxygen-ion conducting ceramic to a reaction front where &agr;-alumina is converted to alkali-metal-&bgr;- or &bgr;&Prime;-alumina. A stabilizer for alkali-metal-&bgr;&Prime;-alumina is preferably introduced into the &agr;-alumina/oxygen-ion conductor composite or introduced into the vapor used to convert the &agr;-alumina to an alkali-metal-&bgr;&Prime;-alumina.

Alkali-metal-&bgr;- and &bgr;&Prime;-alumina and gallate polycrystalline ceramics and fabrication by a vapor phase method

A method of separating oxygen from an oxygen containing gas with a composite membrane capable of conducting oxygen ions and electrons. In accordance with the method, the composite membrane is subjected to an operational temperature and the oxygen containing gas at a cathode side thereof. The composite membrane has a dense layer, at least one active porous layer contiguous to the dense layer, and at least one porous support layer. The active porous layer has a thickness and a distribution of pore radii. The distribution of pore radii has a standard deviation from a theoretical radius that would produce a maximum operation flux through the thickness when the thickness is about equal to a product of a constant and the square root of the theoretical radius. The constant is a function of a material used to fabricate the active porous layer, the operational temperature and an oxygen partial pressure within the active porous layer, and a porosity and a tortuosity produced by the pore radii. The standard deviation of the log of the theoretical radius is equal to a product of 1.45 and a shape factor, the shape factor being greater than 0 and no greater than about 0.5.

Method of separating oxygen with the use of composite ceramic membranes

A solid oxide fuel cell interconnector having a superalloy metallic layer with an anode-facing face and a cathode-facing face and metal layer on the anode-facing face of the superalloy metallic layer. The metal layer is a metal which does not oxidize in a fuel atmosphere, preferably nickel or copper.

Solid oxide fuel cell interconnector

A t&prime;-phase zirconia shapes with superior properties are made by forming a zirconia powder containing a rare-earth-oxide dopant into sintered bodies. The sintered bodies are heat treated in an oxygen atmosphere at a temperature high enough to form a cubic phase. The heated body is then cooled rapidly to form a t&prime;-phase. The t&prime;-phase is characterized with a large grain size, is resistant to transformation, low temperature degradation, and has excellent toughness, and creep resistance. Rare earth-oxide dopants include yttria, scandia, erbia, and ceria. For yttria doped materials, the sintered body is doped with between 2.5 and 5 mole percent yttria.

t&prime;-phase zirconias for high temperature applications

The present invention concerns a high power density solid oxide fuel cell having a cathode, electrolyte and graded porous anode. The graded porosity of the anode allows easy transport of fuel gases thereby minimizing concentration polarization. Power densities of about 1.8 W/cm,at 800&deg; C. and about 0.8 W/cm,at about 650&deg; C. have been achieved with graded porous anodes as thick as 0.75 mm. These fuel cells having a graded porous anode are more durable and mechanically reliable than those found in the art.

High power density solid oxide fuel cell having a graded anode

Method for forming t'-phase zirconia for high temperature applications

A ceramic composite containing alkali-metal-.beta.- or .beta.'-alumina and an oxygen-ion conductor is fabricated by converting .alpha.-alumina to alkali-metal-.beta.- or .beta.'-alumina. A ceramic composite with continuous phases of .alpha.-alumina and the oxygen-ion conducting ceramic, such as zirconia, is exposed to a vapor containing an alkali-metal oxide, such as an oxide of sodium or potassium. Alkali metal ions diffuse through alkali-metal-.beta.- or .beta.'-alumina converted from .alpha.-alumina and oxygen ions diffuse through the oxygen-ion conducting ceramic to a reaction front where .alpha.-alumina is converted to alkali-metal-.beta.- or .beta.'-alumina. A stabilizer for alkali-metal-.beta.'-alumina is preferably introduced into the .alpha.-alumina/oxygen-ion conductor composite or introduced into the vapor used to convert the .alpha.-alumina to an alkali-metal-.beta.'-alumina.

Alkali-metal-.beta.- and .beta.'-alumina and gallate polycrystalline

A solid oxide fuel cell stack having a plurality of integral component fuel cell units, each integral component fuel cell unit having a porous anode layer, a porous cathode layer, and a dense electrolyte layer disposed between the porous anode layer and the porous cathode layer. The porous anode layer forms a plurality of substantially parallel fuel gas channels on its surface facing away from the dense electrolyte layer and extending from one side to the opposite side of the anode layer, and the porous cathode layer forms a plurality of substantially parallel oxidant gas channels on its surface facing away from the dense electrolyte layer and extending from one side to the opposite side of the cathode. A flexible metallic foil interconnect is provided between the porous anode and porous cathode of adjacent integral component fuel cell units.

Planar solid oxide fuel cell stack with metallic foil interconnect

A solid oxide fuel cell interconnector having a superalloy metallic layer with an anode facing face and a cathode facing face and a metal layer on the anode facing face of the superalloy metallic layer, the metal layer including a metal which reacts with Cr.sub.2 O.sub.3 to form an electronically conducting oxide phase on the superalloy metallic layer. In accordance with one particularly preferred embodiment, a second metal layer is disposed between the metal layer and the superalloy metallic layer, the second metal layer including a metal which does not oxidize in a fuel atmosphere.

A gas sensor is provided, having an electrolyte membrane, a sensing electrode, a counter electrode, a diffusion barrier for controlling access of gases to the sensing electrode, and in situ means for removing molecular oxygen from the gases to which the sensing electrode is being exposed.

Multi-functional and NO.sub.x sensor for combustion systems

Growing community of inventors

Salt Lake City, UT, United States of America

Anil Vasudeo Virkar