EP1042666A1 - Detecteur a oxyde metallique permettant la detection d'oxydes d'azote - Google Patents

Detecteur a oxyde metallique permettant la detection d'oxydes d'azote

Info

Publication number
EP1042666A1
EP1042666A1 EP98959588A EP98959588A EP1042666A1 EP 1042666 A1 EP1042666 A1 EP 1042666A1 EP 98959588 A EP98959588 A EP 98959588A EP 98959588 A EP98959588 A EP 98959588A EP 1042666 A1 EP1042666 A1 EP 1042666A1
Authority
EP
European Patent Office
Prior art keywords
sensor
catalyst
metal oxide
sensor system
exhaust gas
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP98959588A
Other languages
German (de)
English (en)
Inventor
Margaret K. Faber
Yuming Xie
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Corning Inc
Original Assignee
Corning Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Corning Inc filed Critical Corning Inc
Publication of EP1042666A1 publication Critical patent/EP1042666A1/fr
Withdrawn legal-status Critical Current

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
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
    • G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
    • 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
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
    • G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
    • G01N27/125—Composition of the body, e.g. the composition of its sensitive layer
    • 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
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
    • B01J23/42—Platinum
    • 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
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
    • B01J23/8906—Iron and noble metals
    • 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
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
    • B01J23/8926—Copper and noble metals
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G19/00—Compounds of tin
    • C01G19/02—Oxides
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/0004—Gaseous mixtures, e.g. polluted air
    • G01N33/0009—General constructional details of gas analysers, e.g. portable test equipment
    • G01N33/0027—General constructional details of gas analysers, e.g. portable test equipment concerning the detector
    • G01N33/0036—General constructional details of gas analysers, e.g. portable test equipment concerning the detector specially adapted to detect a particular component
    • G01N33/0037—NOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02518—Deposited layers
    • H01L21/02521—Materials
    • H01L21/02524—Group 14 semiconducting materials
    • H01L21/02535—Group 14 semiconducting materials including tin
    • 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
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

Definitions

  • the invention relates to a gas sensor system for detecting low concentrations of NO ⁇ in a flowing gas stream and more particularly to a gas sensor system having increased sensitivity for NO x , comprising a sensor oxidation catalyst and a n-type metal oxide semiconductor sensor.
  • Catalytic converters have been used on gasoline-fueled automobiles produced in the United States since the mid-1970's for the purpose of promoting the oxidation of unburned hydrocarbons (HCs) and of carbon monoxide (CO). Soon after their introduction, the converters were adapted to promote the chemical reduction of oxides of nitrogen (NO x ). At the present time these converters typically employ small amounts of platinum, palladium and rhodium dispersed over a high surface area particulate carrier vehicle which, in turn, is distributed as a thin, porous coating (sometimes called a washcoat) on the wall of a ceramic monolith substrate. These flow-through catalytic devices are housed in a suitable stainless steel container and placed in the exhaust stream under the vehicle downstream from the engine's exhaust manifold.
  • this legislation requires that the exhaust from the catalytic converter be monitored, to determine when the steady-state conversion of regulated gases, such as the non-methane hydrocarbons, NO x , and CO, falls below between about 60-80%.
  • regulated gases such as the non-methane hydrocarbons, NO x , and CO
  • OBD-II legislation requires that for low emission vehicles the catalyst is considered to be malfunctioning when the HC, NO x , or CO emissions exceed 1.75 times the Federal Test Procedure (FTP) standard. Given these conditions, there is a strong interest in incorporating additional sensors to the vehicle; e.g., specifically NO x sensors. For a NO x sensor to be effective and useful there are certain requirements which the they must exhibit, including the ability to operate at temperatures from 200-800°C, as well as the ability to sense NO x concentrations as low as 25 ppm to those as high as 2,000 ppm.
  • FTP Federal Test Procedure
  • metal oxide semiconducting materials can be used as chemical sensors for detecting specific components of test gases, e.g., NO x in internal combustion engine exhaust gas. Ceramics which have been utilized include, SnO , doped SnO 2 (Ti, In), TiO 2 , WO 3 , Fe 2 O 3 , ZnO, LaFeO 3 , NiO-ZnO, Cr 2 O 3 -Nb 2 O 5 and YBa 2 Cu 3 O x , among many others.
  • the advantages of these materials for gas sensor applications are several.
  • the samples can readily be prepared as thin or thick films by methods including ion-beam sputtering, magnetron sputtering, screen printing, and sol-gel processing. Depending on the test conditions and the nature of the sample, these sensors can detect gases in concentrations ranging from 10 ppm to > 1,000 ppm. Response times as low as 1 second or less have been reported.
  • Tin oxide (SnO 2 ) is a preferred metal oxide semiconducting material, and thus is widely used as the basis of solid state sensors.
  • Tin (IV) oxide is an n-type semiconductor in which electrical conductivity occurs through negative charge carriers.
  • the mechanism by which semiconducting ceramics such as SnO 2 respond to gases is by a change in the surface resistance of the materials upon the adsorption of a gas.
  • the adsorbing gases react with the surface oxides on the SnO 2 .
  • the resistance increases upon the absorption of an oxidizing gas such as NO x (NO or NO 2 ), and decreases upon the adsorption of a reducing gas such as CO. This can described via the following reactions.
  • U.S. Pat. No. 5,624,640 discloses a sensor having increased sensitivity for detecting nitrogen oxides in a test gas.
  • This sensor comprises a semiconducting metal oxide layer which is deposited on a ceramic substrate and whose electrical resistance provides information about the concentration of nitrogen oxides.
  • the main components of the sensor comprise a converter layer which is deposited on the metal oxide layer and is made of a material which cause the oxidation of the combustible components of the test gas and converts the NO in the test gas into NO 2 or N 2 O .
  • the converter layer comprises TiO and/or ZrO and/or SiO 2 and/or Al 2 O 3 and has a platinum content.
  • the sensor system for measuring the NO x concentration of a flowing gas stream comprises a sensor oxidation catalyst capable of both oxidizing CO and NO in the gas sample to CO 2 and NO 2 , respectively.
  • the catalyst is inco ⁇ orated into the system so as to oxidize the CO and NO in the flowing gas stream prior to the gas stream contacting a metal oxide semiconducting sensor.
  • an n- type semiconducting metal oxide sensor preferably tin oxide, whose electrical resistance varies in relation to the concentration of nitrogen oxides in the flowing gas stream.
  • the semiconductor metal oxide sensor comprises tin oxide (SnO 2 ) and the oxidation catalyst inco ⁇ orated within the system is capable of oxidizing NO and/or
  • CO in the temperature range of between about 200-500°C; more preferably in the temperature range of between about 250-400°C
  • FIG. 1 is a block/flow diagram of the inventive sensor system
  • FIG. 2 is a schematic diagram of an exhaust system inco ⁇ orating one embodiment of an inventive sensor system for measuring the NO x concentration of an exhaust gas stream
  • the present invention is directed at a system for measuring the NO x concentration of a gas sample.
  • the system comprises a sensor oxidation catalyst and a downstream-positioned metal oxide semiconductor sensor, the sensor having an electrical resistance which varies in relation to the concentration of nitrogen oxides (NO x ) in the flowing gas stream.
  • the sensor catalyst is capable of both oxidizing CO and NO in the gas sample to CO 2 and NO 2 respectively, the catalyst being positioned upstream of the metal oxide semiconducting to oxidize the CO and NO in the flowing gas stream prior to the gas stream contacting the metal oxide semiconducting sensor.
  • a main catalytic converter 12 is located in the exhaust gas downstream of an internal combustion engine.
  • the main catalytic converter 12 is capable of catalyzing the exhaust gas so as to reduce the pollutants present in the exhaust gas.
  • the catalyst is a three-way catalyst which functions to oxidize both HCs and CO, as well as to reduce NO x , in the exhaust gas.
  • the sensor system 10 generally comprises a sensor oxidation catalyst 14 and a n- type metal oxide semiconductor sensor 16 for directly measuring the NO x concentration in the exhaust gas.
  • the sensor system 10 includes a housing 18, located downstream of the catalytic converter 12, within which are disposed both the sensor oxidation catalyst 14 and the metal oxide semiconductor sensor 16; supports 16A and 16B are used to support the sensor 16. Furthermore, the sensor communicates with a resistance measuring device which measures the increase of the electrical resistance of the metal oxide semiconducting sensor 16 in a known manner.
  • the housing, sensor catalyst and the sensor could be located upstream of the main converter, thereby functioning to measure the concentration of an upstream portion of exhaust gas.
  • FIG. 3 illustrated therein is another embodiment of the sensor system, wherein the tubular housing 26, is not only located downstream of the main catalytic converter 12, but is remote or off-line from the main flow of the exhaust gas.
  • the sensor oxidation catalyst 28 comprises a tubular body comprised of a catalyst-support material and upon which a catalytically active metal material is deposited; one benefit of this embodiment is that the tubular sensor oxidation catalyst 28 can be uniformly heated by a heater 30 which surrounds the sensor oxidation catalyst thereby ensuring and accelerating the oxidation of the CO and NO in the flowing exhaust gas stream.
  • the metal oxide semiconductor sensor 16 is located within a separate downstream housing portion 32.
  • the metal oxide sensor utilized in the aforementioned two embodiments comprises any conventional metal oxide sensor, including, for example, SnO 2 , In 2 O 3 , Fe 2 O , ZnO, TiO , WO 3 , Nb 2 Os and the like.
  • the preferred metal oxide sensor suitable for use in the instant invention, are disclosed in the following U.S. Patents., Pat. Nos. 4,592,967 (Ko atsu et al.), 4,535,351 (Sakai) and 5,427740 (Coles et al.).
  • the metal oxide sensor may include a heater which increases the conductivity of the metal oxide.
  • the suitable catalyst support material comprises an oxygen storage support material such as ceria-alumina, or preferentially, ceria-stabilized zirconia. Both oxygen storage support materials may result in improved activity of the catalyst for low temperature NO oxidation, as well as low temperature CO oxidation. Since normal engines typically operate at a slightly rich A/F ratio, i.e., an A/F ratio around 14.6, more oxygen is required during these rich conditions so as to ensure that this second catalytic reaction occurs and thus this downstream sensor functions properly. Although excess oxygen can be supplied by providing an air supply line, or the like, to the exhaust gas, it is preferred that the excess oxygen be supplied through the use of these catalyst-support materials comprised of an oxygen storage material. In this case, the catalyst-support materials are capable of storing and releasing oxygen depending upon the widely and rapidly varying oxygen concentration in the exhaust stream.
  • the oxidation catalyst improves the selectivity and response of n-type metal oxide to NO x gases, by combining the metal oxide with suitable catalysts.
  • Suitable catalytically active materials improve the responses of the metal oxide, e.g., tin oxide, both by (1) oxidizing CO (to which tin oxide responds) to CO 2 (to which tin oxide does not respond), thus removing the interfering signal of CO, and (2) more especially, by oxidizing NO to NO 2 .
  • the ability to oxidize NO to NO 2 improves the response of the sensors to the NO x emissions from auto exhaust, since the NO x portion of the exhaust consists of approximately 90% NO and 10% NO 2 .
  • SnO 2 it is more responsive to NO 2 than to NO, and the presence of NO tends to decrease the response to NO 2 .
  • the catalyst serves to either fully oxidize the NO to NO 2 , and/or to maintain the molar ratio of NO to NO 2 at the equilibrium value for a given temperature.
  • the advantage is that the sensor response no longer varies as the NO/NO 2 ratio varies, but gives a constant output that is dependent only on the total [NO+ NO ] concentration. It is also desirable to have the catalyst sufficiently active for NO oxidation and/or
  • catalytically active materials include, for example, Pt, CuO-Pt, Fe 2 -CuO-Pt.
  • the catalytically active material may be comprised of Rh.
  • the catalyst support material comprise the aforementioned oxygen storage support material; i.e., either ceria-alumina or ceria-stabilized zirconia.
  • Rh catalyst supported on ceria-stabilized zirconia is most suitable for applications where the NO x sensors would be primarily used for NO x detection for engine management in lean burn gasoline engines or diesel engines. In these highly oxidizing environments (6% O 2 ), the Rh catalyst may no longer be active for NO x reduction, but may be very suitable for relatively low temperature NO x oxidation.
  • novel low temperature CO oxidation catalytically active material/support material combinations which may be used in the invention described herein include Au supported on MnO 2 , TiO 2 , Fe 2 O 3 or other oxides, as well as perovskite catalysts (e.g., LaCoO 3 ) alone or supported on ⁇ -alumina.
  • the amount of the catalytically active metal material present in the sensor oxidation catalyst will be at least an effective amount and will depend, for example, on required catalyst activity, ease of uniform dispersion, and the type of substrate utilized. Generally, however, the level of catalytically active metal present will range from about 0.01% to 5.0%. and more preferably, 0.01% to 3.5%.
  • the catalytically active material can be applied onto the catalyst-support material by any known method such as for example, by conventional washcoat or spraying techniques.
  • the substrate is contacted with a slurry containing the catalytically active material and other components such as temporary binders, permanent binders or precursors, dispersants and other additives as needed.
  • a slurry containing the catalytically active material and other components such as temporary binders, permanent binders or precursors, dispersants and other additives as needed.
  • the slurry is then applied (for example, by repeated spraying, dipping or vacuum suction) to the substrate until the desired amount of catalytically active material has been applied.
  • a semiconducting metal oxide layer 38 of a thickness of 10-500 ⁇ m is suitably deposited over the strip conductors in the area of the interlocking ends; these strips communicate with a resistance measuring device which, as before, detects and measures any increase in electrical resistance of the semiconducting metal oxide layer 38.
  • the metal oxide semiconductor comprises an n-type semiconductive metal oxide, preferably tin oxide (SnO 2 ).
  • a sensor oxidation catalyst layer 40 is deposited at a suitable thickness of 10-100 ⁇ m over the metal oxide semiconducting layer; it is preferably comprised of the catalytically active metal material described above.
  • the underside of the substrate is provided with a heater 42 which, as described before, is capable of both increasing the conductivity of the metal oxide and of ensuring and accelerating the oxidation of the NO and CO.
  • a heater 42 which, as described before, is capable of both increasing the conductivity of the metal oxide and of ensuring and accelerating the oxidation of the NO and CO.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Biochemistry (AREA)
  • Analytical Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Materials Engineering (AREA)
  • Electrochemistry (AREA)
  • Food Science & Technology (AREA)
  • Combustion & Propulsion (AREA)
  • Medicinal Chemistry (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)

Abstract

L'invention concerne un système de détection permettant de détecter les oxydes d'azote dans un flux de gaz circulant. Ce système comprend un catalyseur d'oxydation de détecteur capable d'oxyder aussi bien le CO que le NO dans l'échantillon gazeux, de manière à former du CO2 et NO2 respectivement. Ce catalyseur est incorporé dans le système de manière à oxyder le CO et le NO dans un flux gazeux avant que ce dernier n'entre en contact avec un détecteur à MOS. L'invention concerne en outre un détecteur à MOS de type N, dont la résistance électrique varie en fonction de la concentration d'oxydes d'azote dans le flux gazeux.
EP98959588A 1997-12-31 1998-12-01 Detecteur a oxyde metallique permettant la detection d'oxydes d'azote Withdrawn EP1042666A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US7027297P 1997-12-31 1997-12-31
US70272P 1997-12-31
PCT/US1998/025118 WO1999034199A1 (fr) 1997-12-31 1998-12-01 Detecteur a oxyde metallique permettant la detection d'oxydes d'azote

Publications (1)

Publication Number Publication Date
EP1042666A1 true EP1042666A1 (fr) 2000-10-11

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ID=22094264

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98959588A Withdrawn EP1042666A1 (fr) 1997-12-31 1998-12-01 Detecteur a oxyde metallique permettant la detection d'oxydes d'azote

Country Status (4)

Country Link
EP (1) EP1042666A1 (fr)
KR (1) KR20010033717A (fr)
CN (1) CN1285914A (fr)
WO (1) WO1999034199A1 (fr)

Cited By (1)

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Publication number Priority date Publication date Assignee Title
WO2022008782A1 (fr) 2020-07-10 2022-01-13 Consejo Superior De Investigaciones Cientificas Détecteur chimique résistif pour la détection de no2

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KR100477422B1 (ko) * 2002-01-11 2005-03-23 동양물산기업 주식회사 암모니아 가스 검지용 반도체식 박막 가스 센서의 제조방법 및 센서 소자
CN1296702C (zh) * 2003-09-30 2007-01-24 鸿富锦精密工业（深圳）有限公司 氧化锌气体感测装置
JP4634720B2 (ja) * 2004-01-20 2011-02-16 サントリーホールディングス株式会社 ガス検出方法および検出装置
JP5012036B2 (ja) * 2007-01-17 2012-08-29 トヨタ自動車株式会社 硫黄成分検出装置
KR101113315B1 (ko) * 2009-11-06 2012-03-13 광주과학기술원 촉매층을 구비하는 가스센서 및 이의 동작방법
US9389212B2 (en) 2011-02-28 2016-07-12 Honeywell International Inc. NOx gas sensor including nickel oxide
CN102806091B (zh) * 2012-06-29 2016-03-09 中国第一汽车股份有限公司 一种可用于NOx检测的新型复合催化剂材料
CN102980916A (zh) * 2012-11-19 2013-03-20 中国科学院上海硅酸盐研究所 氧化锆基NOx传感器及其制备方法
CN104792846B (zh) * 2014-12-10 2017-10-03 中国第一汽车股份有限公司 可用于nox传感器的多功能防护罩及其涂层制备方法
TWI579561B (zh) * 2016-06-22 2017-04-21 國立成功大學 二氧化鈰酸鹼値感測器及其製造方法
CN106093140B (zh) * 2016-07-19 2019-10-25 山东大学 针对no2气体的复合结构掺杂气敏材料、气敏元件及其制作方法与应用
US10942157B2 (en) * 2018-02-21 2021-03-09 Stmicroelectronics Pte Ltd Gas sensor device for detecting gases with large molecules
CN110687104B (zh) * 2019-11-12 2021-08-13 北京联合大学 一种一氧化碳和三甲胺的交叉敏感材料
CN112067607B (zh) * 2020-09-09 2022-04-15 深圳九星印刷包装集团有限公司 一氧化碳指示装置

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022008782A1 (fr) 2020-07-10 2022-01-13 Consejo Superior De Investigaciones Cientificas Détecteur chimique résistif pour la détection de no2

Also Published As

Publication number Publication date
CN1285914A (zh) 2001-02-28
KR20010033717A (ko) 2001-04-25
WO1999034199A1 (fr) 1999-07-08

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