Abstract: Embodiments of the subject invention relate to a gas sensor and method for sensing one or more gases. An embodiment incorporates an array of sensing electrodes maintained at similar or different temperatures, such that the sensitivity and species selectivity of the device can be fine tuned between different pairs of sensing electrodes. A specific embodiment pertains to a gas sensor array for monitoring combustion exhausts and/or chemical reaction byproducts. An embodiment of the subject device related to this invention operates at high temperatures and can withstand harsh chemical environments. Embodiments of the device are made on a single substrate. The devices can also be made on individual substrates and monitored individually as if they were part of an array on a single substrate. The device can incorporate sensing electrodes in the same environment, which allows the electrodes to be coplanar and, thus, keep manufacturing costs low.

Abstract: A device for the concurrent oxygen generation and control of carbon dioxide for life support system involves two stages, where a first stage removes CO2 from an exhalent side of a ventilation loop and a second stage employs Ceramic Oxygen Generators (COGs) to convert CO2 into carbon and O2. The first stage includes a plurality of chambers and means to switch the ventilation loop through at least one of the chambers, where CO2 removal is carried out before discharge of the CO2 depleted gas to an inhalant side of the ventilation loop, and to exclude the ventilation loop from the remaining chambers of the first stage, where these chambers are placed in communication with the second stage. The second stage has two portions separated by the COGs such that CO2 and the formed carbon remain on an intake portion from the O2 rich atmosphere on the exhaust side, which is plumbed via a metering valve to introduce the O2 rich atmosphere to the inhalant side of the ventilation loop.

Abstract: A solid state electrochemical cell (10a) for measuring the concentration of a component of a gas mixture (12) includes first semiconductor electrode (14) and second semiconductor electrode (16) formed from first and second semiconductor materials, respectively. The materials are selected so as to undergo a change in resistivity upon contacting a gas component, such as CO or NO. An electrolyte (18) is provided in contact with the first and second semiconductor electrodes. A reference cell can be included in contact with the electrolyte. Preferably, a voltage response of the first semiconductor electrode is opposite in slope direction to that of the second semiconductor electrode to produce a voltage response equal to the sum of the absolute values of the control system uses measured pollutant concentrations to direct adjustment of engine combustion conditions.

Abstract: A solid state electrochemical cell for measuring the concentration of a component of a gas mixture includes a first semiconductor electrode and a second semiconductor electrode, the electrodes formed from first and second semiconductor materials, respectively. The materials are selected so as to undergo a change in resistivity upon contacting a gas component, such as CO or NO. An electrolyte is provided in contact with the first and second semiconductor electrodes. A reference cell can be included in contact with the electrolyte. Preferably, a voltage response of the first semiconductor electrode when exposed to the component is opposite in slope direction to that of the second semiconductor electrode to produce a voltage response equal to the sum of the absolute values of the individual voltages generated. A combustion engine includes an emission sensor for measuring pollutants and a feedback and control system uses measured pollutant concentrations to direct adjustment of engine combustion conditions.

Abstract: An ionic conductor has been developed which exhibits both hydrogen ion conductivity and electronic conductivity. The conductor is a perovskite-type oxide represented by the general formula: ABO3 where A consists of at least one element selected from the group consisting of Ba, Ca, Mg and Sr and B is Ce1−xMx where M is a multivalent dopant metal, preferably Eu or Tb, and x is greater than 0 and less than 1. It is particularly useful in processes in which hydrogen is separated from a hydrogen-containing gas, e.g. in conversion of natural gas, operation of hydrogen fuel cells, etc.

Abstract: An ionic conductor has been developed which exhibits both hydrogen ion conductivity and electronic conductivity. The conductor is a perovskite-type oxide represented by the general formula: ABO3 where A consists of at least one element selected from the group consisting of Ba, Ca, Mg and Sr and B is Ce1-xMx where M is a multivalent dopant metal, preferably Eu or Tb, and x is greater than 0 and less than 1. It is particularly useful in processes in which hydrogen is separated from a hydrogen-containing gas, e.g. in conversion of natural gas, operation of hydrogen fuel cells, etc.

Abstract: A two-phase proton and electron conductor is described which comprises (a) a proton conductive oxides represented by the formula: ABO3 where A is selected from the group consisting of Ba, Ca, Mg and Sr and B is Ce1−xMx or Zr1−xMx, where x has a value greater than zero and less than one and M is an element selected from the group consisting of Y, Yb, In, Gd, Nd, Eu, Sm and Tb, in combination with (b) an electron conductor comprising palladium. The palladium may be coated on particles of the oxide in the form of an oxide powder. This novel two-phase conductor is particularly useful as a mixed hydrogen ion and electronic conducting membrane for separating hydrogen from a hydrogen-containing gas.

Abstract: Stable high conductivity functionally gradient compositionally layered solid bodies suitable for use as electrolytes and membranes and providing improved oxygen-ion conductivity for electrolytes and improved mixed oxygen-ion and electronic conductivity for membranes. The electrolytes provide solid oxide fuel cells with high efficiency operation at 300.degree. to 800.degree. C.

Abstract: Stable high conductivity functionally gradient compositionally layered solid bodies suitable for use as electrolytes and membranes and providing improved oxygen-ion conductivity for electrolytes and improved mixed oxygen-ion and electronic conductivity for membranes. The electrolytes provide solid oxide fuel cells with high efficiency operation at 300.degree. to 800.degree. C.

Abstract: Sensors (10, 40) accurately measure the concentration of an oxide compound, such as nitrogen oxide NO.sub.x, in a gas mixture (11) which can include oxygen O.sub.2. The sensors (10, 40) each comprise a chamber (12, 42) adapted to receive the gas mixture (11) as well as first and second electrochemical cells (16, 17) for consuming oxygen and/or the oxide compound in the chamber (12, 42). The first electrochemical cell (16) comprises a first internal electrode (16a) inside the chamber (12, 42), a first external electrode (16b) outside the chamber (12, 42), and a first electrolyte body (14') therebetween. The second electrochemical cell (17) comprises a second internal electrode (17a) inside the chamber (12, 42), a second external electrode (17b) outside the chamber (12, 42), and a second electrolyte body (14") therebetween. The first and second electrolyte bodies (14', 14") are permeable to oxygen ions.