Abstract: A particulate matter sensor includes a first sensing electrode and a second sensing electrode spaced away from the first sensing electrode such that an electrode gap is formed between the first sensing electrode and the second sensing electrode upon which particulate matter is collected, thereby changing conductance between the first sensing electrode and the second sensing electrode. An ionic conductive material is in electrical communication with the first sensing electrode and the second sensing electrode.

Abstract: A particulate matter sensor includes a first sensing electrode and a second sensing electrode spaced away from the first sensing electrode such that an electrode gap is formed between the first sensing electrode and the second sensing electrode upon which particulate matter is collected, thereby changing conductance between the first sensing electrode and the second sensing electrode. An ionic conductive material is in electrical communication with the first sensing electrode and the second sensing electrode.

Abstract: A method for fault identification of gas sensors exposed to a gas mixture is disclosed for gas sensors having an output that depends on concentrations of two gas species in the gas mixture. The method includes receiving output signals from two such sensors, processing the output signals in a controller that implements a model of the sensors so as to identify a fault in the first gas sensor or the second gas sensor; and providing an indication of any identified faults.

Abstract: A method and device allow the determination of the concentrations of a plurality of gas species in a gas mixture based on the output signals from a plurality of gas sensors, each of which is sensitive to a plurality of gas species in the gas mixture. The method includes measuring the response of each sensor at a number of levels of each gas in the mixture, determining a mathematical representation of the response characteristics of each sensor, and using the mathematical representation to determine gas concentrations from sensor readings.

Abstract: A method for fault identification of gas sensors exposed to a gas mixture is disclosed for gas sensors having an output that depends on concentrations of two gas species in the gas mixture. The method includes receiving output signals from two such sensors, processing the output signals in a controller that implements a model of the sensors so as to identify a fault in the first gas sensor or the second gas sensor; and providing an indication of any identified faults.

Abstract: A method and device allow the determination of the concentrations of a plurality of gas species in a gas mixture based on the output signals from a plurality of gas sensors, each of which is sensitive to a plurality of gas species in the gas mixture. The method includes measuring the response of each sensor at a number of levels of each gas in the mixture, determining a mathematical representation of the response characteristics of each sensor, and using the mathematical representation to determine gas concentrations from sensor readings.

Abstract: An exhaust gas sensing system and a method for determining concentrations of exhaust gas constituents are provided. The exhaust gas sensing system includes a NH3 sensing cell, a NO2 sensing cell, a NOx pumping cell, and a current sensor that detects an electrical current flowing through the NOx pumping cell. A computer determines a NO2 concentration value, a NH3 concentration value, a NO concentration value, and a NOx concentration value based on signals from the NH3 sensing cell, the NO2 sensing cell, and the current sensor.

Abstract: A NOX sensor material includes a composition of Ba(1-X)AXFe(12-Y)BYO19. Constituent A and constituent B are doping elements. Constituent A is selected from the group consisting of Bi, La and Pb and X is a real number where 0?X<1. Constituent B is selected from the group consisting of Al, B, Bi, Ca, Co, Cr, Cu, Er, Ga, In, Mg, Mn, Ni, Nb, Rh, Pb, Si, Sr, Ti, Ta, Zn and Zr and Y is a real number where 0?Y<12. The NOX sensor material may be used in a sensor element of a NOX sensor.

Abstract: A system and a method for monitoring operation of an exhaust gas treatment system using an exhaust gas sensor in accordance with an exemplary embodiment is provided. The exhaust gas treatment system has an exhaust pipe configured to receive exhaust gases. The exhaust gas treatment system has an SCR catalyst coupled to the exhaust pipe. The exhaust gas treatment system has a urea delivery system configured to delivery urea upstream of the SCR catalyst. The exhaust gas sensor has an ammonia sensing electrode communicating with exhaust gases downstream of the SCR catalyst. The method includes generating a first output signal utilizing the ammonia sensing electrode, the first output signal being indicative of a first ammonia level. The method further includes generating a second output signal to induce the urea delivery system to deliver a predetermined flow rate of urea upstream of the SCR catalyst. The second output signal is based on the first output signal.

Abstract: An exhaust gas sensing system and a method for determining concentrations of exhaust gas constituents are provided. The exhaust gas sensing system includes a NH3 sensing cell, a NO2 sensing cell, a NOx pumping cell, and a current sensor that detects an electrical current flowing through the NOx pumping cell. A computer determines a NO2 concentration value, a NH3 concentration value, a NO concentration value, and a NOx concentration value based on signals from the NH3 sensing cell, the NO2 sensing cell, and the current sensor.

Abstract: In an internal combustion engine system having an exhaust aftertreatment system including a selective catalytic reduction (SCR) catalyst, diagnostic methods involve the intrusive perturbation of a target surface coverage parameter theta to determine the state of health of the SCR catalyst or an ammonia concentration sensor. An adaptive learning block adapts the target theta based on the use of NH3 sensing feedback from a mid-brick positioned ammonia concentration sensor to pull in system variation. A further diagnostic monitors the amount of adaptation and when the adaptive learning excessively learns, the diagnostic assumes that some system-level degradation must have occurred and the diagnostic will notify the overall emissions control monitor.

Abstract: A NOX sensor material includes a composition of Ba(1-X)AXFe(12-Y)BYO19. Constituent A and constituent B are doping elements. Constituent A is selected from the group consisting of Bi, La and Pb and X is a real number where 0?X<1. Constituent B is selected from the group consisting of Al, B, Bi, Ca, Co, Cr, Cu, Er, Ga, In, Mg, Mn, Ni, Nb, Rh, Pb, Si, Sr, Ti, Ta, Zn and Zr and Y is a real number where 0?Y<12. The NOX sensor material may be used in a sensor element of a NOX sensor.

Abstract: A gas measurement system includes a sensor element and an associated electronic control unit (ECU) or the like connected thereto for receiving sensor element emf outputs. The ECU is configured to provide output signals or parameters indicative of ammonia and heavy HC gas concentrations. The sensor element has an NH3 sensor electrode output and a NOx sensor electrode output. The information conveyed by the NOx sensor electrode output may be selectively used by the ECU, in accord with so-called emf selection rules, to correct for a cross-interference effect that NO2 has on the NH3 electrode. Heavy HC gas concentrations may cause electrochemical activity on the NH3 electrode, and can be misinterpreted. A further emf selection rule is configured to detect the presence of heavy HC gas and is used by the ECU to suppress an output signal or parameter indicative of an ammonia gas concentration.

Abstract: A single-cell sensor element is configured for ammonia gas sensing. The sensor includes an electrolyte layer, an NH3 sensing electrode and a NOx sensing electrode. The NH3 sensing electrode is sensitive to NH3 but is also vulnerable to cross-interference from NO2. To directly correct for this cross-interference, a second (NOx) electrode is provided and is used in a differential connection arrangement with the NH3 sensing electrode. The NOx sensing electrode has a first electrochemical sensitivity to NO2 that is greater than second and third electrochemical sensitivities to NH3 and NO, respectively. The NOx sensing electrode may have low or no sensitivity to NH3 or NO. The sensor element also includes first and second electrical leads respectively connected to the NH3 and NOx sensing electrodes.

Abstract: Disclosed herein is an ammonia sensor element comprising an ammonia selective sensor electrode, a reference electrode, a solid electrolyte in ionic communication with the ammonia selective sensor electrode and the reference electrode, and a protective layer disposed on the ammonia selective sensor electrode, comprising a porous portion comprising an ammonia-inert material. A method of making an ammonia gas sensor element comprises disposing an ammonia selective sensor electrode on and in ionic communication with a solid electrolyte, disposing a reference electrode on and in ionic communication with the solid electrolyte, and disposing a protective layer comprising a porous portion comprising an ammonia-inert material on the ammonia selective sensor electrode.

Abstract: Exhaust gas sensing system and methods for sensing concentrations of exhaust gas constituents are provided. The exhaust gas sensing system includes a NOx sensing cell configured to generate a voltage in response to exhaust gases communicating with the NOx sensing cell. The exhaust gas sensing system further includes a temperature sensor configured to generate a signal indicative of a temperature of the exhaust gases. The exhaust gas sensing system further includes a controller configured to receive the voltage from the NOx sensing cell and to determine a first NOx value based on the voltage. The controller is further configured to receive the signal from the temperature sensor and to determine a temperature value based on the signal. The controller is further configured to determine a NO2 concentration value indicative of an amount of NO2 in the exhaust gases based on the first NOx value and the temperature value, and to store the NO2 concentration value in a memory device.

Abstract: Disclosed herein is a composition for use in a NOx electrode comprising: Tb(1-x)Ln(x)E(1-y)Q(y1)X(y2)Z(y3)O3 wherein Ln is a lanthanoid or a combination of lanthanoids, E is a metal selected from chromium, iron, and a combination thereof, Q is an element selected from magnesium, calcium, strontium, and a combination thereof, X is an element selected from boron, lead, phosphorus, germanium, and a combination thereof, Z is an element selected from barium, silicon, aluminum, and a combination thereof, x is from 0 to about 0.5, y is from about 0.05 to about 0.8, and y1, y2, y3 are independently from 0 to about 0.8, with the proviso that y=y1+y2+y3, and y2+y3 is greater than 0. Also disclosed are a method of making it, electrodes and sensors comprising it, and a method of detecting NOx.