Delphi Technologies, Inc.

Gm Global Technolgoy Operations, Inc.

Kailash Chandra Jain

Bernard A MacIver

Da Yu Wang

Paul Casey Kikuchi

Rick Daniel Kerr

Joseph M Keller

Joseph V Bonadies

Carlos Augusto Valdes

Eric P Clyde

Kenneth M Rahmoeller

Jacob A Abraham

Stephen J Valeri

Su-Chee Simon Wang

Bryan A Gillispie

Eric J Detwiler

Robert Gregory Fournier

David Thompson

Mohammad Parsian

Rod R Stilgenbauer

Matthew Osterhout

Joseph Michael Keller

David Allen Thompson

A cathode of a solid-oxide fuel cell includes a first ionic conducting layer, a second layer deposited over the first layer and formed from a mixed ionic and electronic conductor layer including an oxygen ion conducting phase, and a third layer deposited over the second layer and formed from a mixed ionic and electronic conductor layer. A sintering aid and pore formers are added to the second layer and the third layer to establish ionic, electronic, and gas diffusion paths that are contiguous. By adjusting the microstructure of the second and the third layer, a high performance low resistance cathode is formed that bonds well to the electrolyte, is highly electro-catalytic, and has a relatively low overall resistance. By using inexpensive and readily available substances as sintering aid and as pore formers, a low-cost cathode is provided.

Low-temperature bonding of refractory ceramic layers

A sintered solid composite material is disclosed that includes a metal and a calcium alumina compound. The metal can be a noble metal. This composite material can bond to a ceramic material, and an article is disclosed that includes a first ceramic layer bonded to a second layer of the composite material of metal and calcium alumina compound. The ceramic can be a mixed ionic and electronic conductor (MEIC), and/or have a perovskite crystal structure, and/or be a mixed oxide comprising lanthanum, strontium, cobalt, iron and oxygen. The article can be used as an electrode such as a cathode of a solid oxide fuel cell.

Metal composite material for attachment to ceramic

A solid state sintered material is described that includes a mixed oxide of lanthanum, strontium, cobalt, iron and oxygen, and CaCOinclusions. The solid state sintered material can also include calcium oxide, which can form from thermal composition of calcium carbonate. The solid state sintered material can also include a pore-forming particulate material such as carbon black and/or a doped ceramic metal oxide ionic conductor such as Sm-doped ceria uniformly dispersed in the solid state sintered material. The solid state sintered material can be formed from a two-step process in which a portion of the CaCOis mixed with the mixed oxide materials and heated to form porous agglomerates, and the remaining CaCOis added during the formation of a sintering paste. The solid state sintered material described herein can be used as a cathode material for solid oxide fuel cell.

Material for solid state sintered material

An improved LSCF 6428 perovskite material of the type LaSrCoFeOwherein x=0.4, z=(0-0.1), a=(0.01-0.04), and b=(0.05-0.15) for use as an SOFC cathode having increased electronic and ionic conductivity. The general formula is similar to the prior art formulae (LaSr)CoFeOand LaSrCoFeObut applies the z term to La and Sr independently as well as reducing the overall content of La. Further, by adding a small amount (a) of extra Co ions, catalytic activity, conductivity, and sinterability are further enhanced. Adding small amounts (b) of Fe and/or Fe and Co moderates the thermal expansion coefficient with no adverse effect on crystal structure or fuel cell performance. Improved sinterability, microstructure, and reduced film cracking result in high power density of fuel cells. An inherently low-cost solid state reaction method is described.

Perovskite materials for solid oxide fuel cell cathodes

A method for improving performance of an SOFC by impregnation of the cathode with metallic silver. A solution of AgNOin acetonitrile is imbibed into a perovskite cathode fabricated on a electrolyte layer supported by an anode, defining an SOFC cell. The cathode imbibition may be repeated a plurality of times as may be needed depending upon the thickness of the cathode. The amount of solution soaked into the cathode results a total final weight percent of Ag in the cathode between about 0.5% and about 10%. The cathode is then fired in air at high temperature to drive off the acetonitrile and to reduce the silver ions to metallic silver. In this way, cathode electrical resistance may be reduced by as much as 52%.

Method for impregnating a solid oxide fuel cell cathode with silver to reduce electrical resistance

A two-step chemical treatment method for chemically conditioning a sensor element comprising an electrolyte in ionic communication with a first electrode and a second electrode is described. The method comprises treating at least a portion of a sensor element with a first solution comprising an inorganic base, a carbonate salt and an acid salt; heating the sensor element; treating at least a portion of the sensor element with a second solution comprising an inorganic base and a carbonate salt; and drying the sensor element. The gas sensors comprising the two-step treated sensor elements have reduced lean shift, green effect, sensor output amplitude drop, and the light-off time is improved.

Methods of making gas sensors and sensors formed therefrom

A method of treating a gas sensor comprising: disposing the gas sensor in a basic agent solution comprising a basic agent selected from the group consisting of Group IA of the Periodic Table of Elements, Group IIA of the Periodic Table of Elements, and combinations comprising at least one of the foregoing metals, wherein the gas sensor comprises an electrolyte disposed between and in ionic communication with a first electrode and a second electrode; disposing the gas sensor in an acidic agent solution; wetting at least a portion of a porous protective layer of the gas sensor with an alkaline-carbonate solution; and heating the gas sensor.

Method of treating a gas sensor

Disclosed herein is a method for producing a gas sensor, comprising disposing a reference electrode on a side of an electrolyte, disposing a measuring electrode on a side of the electrolyte opposite the reference electrode, disposing a first protective coating on a side of the measuring electrode opposite the electrolyte, treating the sensor with an aqueous salt solution comprising chloride and carbonate salts comprising elements selected from the group consisting of Group IA and IIA elements of the Periodic Table to form a treated sensor comprising the chloride and the carbonate salt mixture, drying the treated sensor, and disposing a second protective coating on a side of the first protective coating opposite the measuring electrode.

Co-fired oxygen sensor elements

One embodiment of a method for producing a gas sensor, comprises: disposing said gas sensor in a basic agent solution comprising a basic agent comprises a hydroxide of a metal selected from the group consisting of Group IA of the Periodic Table of Elements; Group IIA of the Periodic Table of Elements, and combinations comprising at least one of the foregoing basic agents, wherein said gas sensor comprises an electrolyte disposed between and in ionic communication with a first electrode and a second electrode; and disposing said gas sensor in an acidic agent solution.

Gas sensor and method of manufacturing the same

A titania exhaust gas oxygen sensor including an alumina substrate, thin-film electrodes deposited thereon, and a thick-film titania layer deposited atop the electrodes. The electrodes comprise a noble metal (e.g., platinum) having a plurality of titania particles dispersed throughout for promoting bonding to the titania, resistive layer when the titania layer is fired.

Titania exhaust gas oxygen sensor

A method for preferentially etching phosphosilicate glass to form a micromechanical structure includes forming a layer of phosphosilicate glass on a substrate and opening at least one via in the phosphosilicate glass layer. A layer of material which is patterned to produce a micromechanical structure is formed over the phosphosilicate glass layer which extends through the via and adheres to the substrate. The phosphosilicate glass layer is then removed by immersing the device in an etchant bath containing an aqueous ammoniacal hydrogen peroxide solution. The resulting micromechanical structure has at least one point of attachment to the substrate and is otherwise spaced apart from the substrate by an air gap. A method for attaching an overhanging mass to a miniature cantilever beam using microelectronics fabrication technology is also provided in which the center of gravity is shifted to the endpoint of the free end of the beam. There is further provided an integrated sensor which includes at least one micromechanical transducing structure and on-board detection circuitry which detects extremely small motions of the structure and produces a corresponding digital output.

Method for fabricating three-dimensional microstructures and a

JMOS depletion mode transistors include back-to-back junctions in the doped polysilicon layer that serves as the gate. The polysilicon layer includes a first region of the same conductivity type as the channel in contact with the channel, and a second region, of the same conductivity type as the channel and to which the gate potential is applied, spaced apart by a region of the opposite conductivity type that serves as a sink for minority carriers in the channel. Both buried oxide layer and recessed gate JMOS transistors are included.

JMOS transistor utilizing polysilicon sinks

A process for forming a buried patterned silicon oxide layer in a silicon chip in which the layer is formed by implanting oxygen into the chip through a mask of silicon oxide on the surface of the silicon chip. The silicon oxide mask is formed to have essentially vertical side walls by interposing an irradiation step between a pair of isotropic wet etching steps in its formation.

Process for forming in a silicon oxide layer a portion with vertical

A vertical depletion mode power field effect transistor having a greatly increased drain-to-source breakdown voltage. The drain region is formed in the substrate and separated from the channel by a first insulative layer having apertures which allow the passage of electrical currents. The channel, which is formed between the first insulative layer and a second insulative layer parallel to the substrate surface, contains both a source region, formed by implantation of impurities of the same type as are used to form the drain region, and a gate region. In this configuration, the normally high voltage which exists between the gate and drain is imposed over a greater distance than in conventional depletion mode vertical FETs, so that this new configuration produces vertical power FETs having much higher breakdown voltages than do conventional depletion mode vertical FETs. Islands having a conductivity type opposite to that used to form the source region are formed immediately below the second insulative layer and serve to prevent the creation of a charge inversion layer in the channel, where the inversion layer adversely affects the turn off characteristic of the j-MOS power transistor.

Growing community of inventors

Troy, MI, United States of America

Kailash Chandra Jain