WO1995000836B1 - Semiconducting oxide gas sensors and materials therefor - Google Patents
Semiconducting oxide gas sensors and materials thereforInfo
- Publication number
- WO1995000836B1 WO1995000836B1 PCT/GB1994/001327 GB9401327W WO9500836B1 WO 1995000836 B1 WO1995000836 B1 WO 1995000836B1 GB 9401327 W GB9401327 W GB 9401327W WO 9500836 B1 WO9500836 B1 WO 9500836B1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- sensor
- sensing element
- sensor according
- array
- vii
- Prior art date
Links
- 239000000463 material Substances 0.000 title claims abstract 33
- 239000007789 gas Substances 0.000 claims abstract 18
- 150000002430 hydrocarbons Chemical class 0.000 claims abstract 6
- 229910052760 oxygen Inorganic materials 0.000 claims abstract 6
- 238000001514 detection method Methods 0.000 claims abstract 5
- MYMOFIZGZYHOMD-UHFFFAOYSA-N oxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims abstract 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract 4
- 239000001301 oxygen Substances 0.000 claims abstract 4
- 239000000460 chlorine Substances 0.000 claims abstract 3
- 229910052801 chlorine Inorganic materials 0.000 claims abstract 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims abstract 3
- 150000002148 esters Chemical class 0.000 claims 9
- 238000010438 heat treatment Methods 0.000 claims 6
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims 5
- KYKAJFCTULSVSH-UHFFFAOYSA-N chloro(fluoro)methane Chemical compound F[C]Cl KYKAJFCTULSVSH-UHFFFAOYSA-N 0.000 claims 2
- 238000004519 manufacturing process Methods 0.000 claims 2
- 229910052758 niobium Inorganic materials 0.000 claims 2
- 229910052715 tantalum Inorganic materials 0.000 claims 2
- XGBDPAYTQGQHEW-UHFFFAOYSA-N Ferrate(VI) Chemical compound [O-][Fe]([O-])(=O)=O XGBDPAYTQGQHEW-UHFFFAOYSA-N 0.000 claims 1
- 229910052779 Neodymium Inorganic materials 0.000 claims 1
- 229910052770 Uranium Inorganic materials 0.000 claims 1
- 150000001299 aldehydes Chemical class 0.000 claims 1
- 229910052782 aluminium Inorganic materials 0.000 claims 1
- 229910052787 antimony Inorganic materials 0.000 claims 1
- 229910052797 bismuth Inorganic materials 0.000 claims 1
- 229910052804 chromium Inorganic materials 0.000 claims 1
- 230000001419 dependent Effects 0.000 claims 1
- 150000002170 ethers Chemical class 0.000 claims 1
- 239000001257 hydrogen Substances 0.000 claims 1
- 229910052739 hydrogen Inorganic materials 0.000 claims 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims 1
- 150000002576 ketones Chemical class 0.000 claims 1
- 238000005259 measurement Methods 0.000 claims 1
- 229910052751 metal Inorganic materials 0.000 claims 1
- 239000002184 metal Substances 0.000 claims 1
- 150000002739 metals Chemical class 0.000 claims 1
- 230000000116 mitigating Effects 0.000 claims 1
- 229910052750 molybdenum Inorganic materials 0.000 claims 1
- 239000011148 porous material Substances 0.000 claims 1
- 238000005245 sintering Methods 0.000 claims 1
- 239000002904 solvent Substances 0.000 claims 1
- 229910052718 tin Inorganic materials 0.000 claims 1
- QHGNHLZPVBIIPX-UHFFFAOYSA-N tin(II) oxide Inorganic materials [Sn]=O QHGNHLZPVBIIPX-UHFFFAOYSA-N 0.000 claims 1
- 229910052726 zirconium Inorganic materials 0.000 claims 1
Abstract
The selectivity of response of resistive gas sensors to specific gases or vapours is improved by the selection of specified gas-sensitive materials which are not previously known for the applications described, which include detection of hydrocarbons in the presence of CO, H2S, SO2, chlorine, NO2, CO2 (especially in low concentrations), CFC's, ammonia, free oxygen by determination of partial pressure, and numerous organic gases and vapours.
Claims
1. A gas sensor comprising a semiconducting sensing element such that its electrical resistance changes in response to a change in the concentration of at least one target gas or vapour, whereby the sensing element is selective in favour of the target gas, so as to detect the latter, characterised in that the sensing element is of a material selected from the following materials:
(i) Ba 6Fe,(1+x() b(9-x)030, where 2.1>x>>0;' (ii) A 2B4Fe,(3+xv)Nb,(7-x)030, where A is a divalent element of large ionic size, B is a trivalent element, and 3.l≥xl≥O;
(iii) A 6B4Fe,(4+x,) b,(G-x)030,' where A is a trivalent element of large ionic size, B is a trivalent element, and 4.l≥x≥O;
(iv) Cr (,2-x)Tix03, where 0.3>x>0.05;
(v) Ti (l-x)Crx0(2+y), where 0.2>x>0, and y J is a variable dependent on temperature and on partial pressure of oxygen, -
(vi) Fe (l+x-z)AzNb(l-x)04, where O.l≥x≥O, O.l≥z≥O, and A is selected from the pentavalent and hexavalent metals;
(vii) Fe (l-x)BxNbO4, where B is selected from:
- trivalent elements , with l≥x≥O , and
- tetravalent elements , with O . l≥x≥O ; (viii) (Fe(l-x)CrxN O4)a(B(1-y)AyO2) (1-a)' where l≥a≥O, l≥x≥O.1, 0.l≥y≥O, A is an element of valency greater than 4, and B is Ti or Sn;
(ix) BaSn (l-x)Sbx03, where 0≤x<0.1;
(x) Sr (l-b)BabFe(,1-y)AyO,(3-xv) ' where l≥b≥O, 0.5>x>0, A is an element of valency greater than 5, and y is a fraction of the ferrate lattice replaced by A; and
(xi) o3,
and in that the material is selected as follows in accordance with the following target gases to be detected:
hydrocarbons other than methane (in the presence of CO) : any of (i) to (iii) ;
hydrocarbons other than methane (whether or not CO is present) : any of (i) to (iv) ; (viii) ;
methane: any of (i) to (iii) ;
aldehydes, ketones, ethers, diethers: (iv) ,- (vi) ; (vii) ; (viii) ;
esters, including unsaturated esters: (iv) ; (vi) ; (vii) ; (viii) ;
chlorine or NO : (vi) ; (vii) ; (xi) ;
any oxidising gas (especially in the presence of hydrocarbons and/or CO) : (vi) ; (vii) ;
H2S, S02: (iv) ;
- CO: (iv) ; (viii) ; CO 2 : ( ix) ;
chlorofluorocarbons (CFC) : (viii) ;
ammonia: (iv) ; (vii) ;
free oxygen: (v) ; (x) .
2. A sensor according to Claim 1 in which the sensing element is of material (i) , characterised in that 0.8>x≥0.01.
3. A sensor according to Claim 2, characterised in that x is 0.4 or 0.6.
4. A sensor according to Claim 1 in which the sensing element is of material (ii) , characterised in that A is Pb, and/or B is Nd.
5. A sensor according to Claim 1 in which the sensing element is of material (iii) , characterised in that A is Bi, and/or B is selected from Nd and Bi.
6. A sensor according to Claim 1 in which the sensing element is of material (iv) , characterised in that the sensing element has a microstructure in which the average crystallite diameter and average pore diameter are both smaller than 1 micrometre.
7. A sensor according to Claim 1 in which the sensing element is of material (vi) , characterised in that the pentavalent element is selected from Nb and Ta, and/or the hexavalent element is .
8. A sensor according to Claim 1 in which the sensing element is of material (vii) with B trivalent, characterised in that B is selected from Al and Cr.
9. A sensor according to Claim 1 in which the sensing element is of material (vii) with B tetravalent, characterised in that B is selected from Zr and Ti.
10. A sensor according to Claim 1 in which the sensing element is of material (viii) , characterised in that A is selected from Nb, Ta, and Sb.
11. A sensor according to Claim 1 in which the sensing element is of material (vii) , characterised in that the said material is selected from CrNbO 4 and Fe ( l -x) Cr XNbO i , where l≥x≥O . 1 .
12. A sensor according to Claim 1 in which the sensing element is of material (x) , characterised in that A is selected from , Mo and U.
13. A sensor according to Claim 1 having a WO sensing element, characterised in that the sensing element is in the form of a film, with the sensor including a heating element for heating the film so that the latter, when heated, displays in response to the presence of 0.5 parts per million of chlorine or NO in air a resistance substantially higher than in response to SO or CO.
14. A sensor according to Claim 13, characterised in that the thickness of said film is in the inclusive range 10 - 200 micrometres.
15. A sensor according to Claim 14, characterised in that the said thickness is 100 micrometres.
16. A sensor according to any one of the preceding Claims, including a heating element (17) for heating the sensing element (14) , and electrical connecting means connected variously to the sensing element and heating element, characterised in that said connecting means comprise first connection means (10, 15) connected to the sensing element, and a common electrical connection (20) connected to both of said elements (14, 17) .
17. A sensor according to Claim 16, characterised in that one of the said elements (14, 17) is overlaid on the other so that they work as two resistors in parallel, the said first connection means comprising a further connection common to both of said elements (14, 17) .
18. A sensor array for detecting at least one gas or vapour constituting a target gas, characterised in that the array comprises at least one first sensor, being a sensor according to any one of the preceding Claims, in combination with at least one further sensor having a characteristic response, to at least one said target gas and/or at least one further gas or vapour that may be present, different from that of said first sensor.
19. An array according to Claim 18, characterised in that said first sensor is a sensor according to Claim l in which the sensing element is of material (vii) with B being trivalent and l≥x≥O, a said further sensor being a sensor according to Claim 1 having its sensing element material selected from material (iv) and material (vii) , with, in the latter case B trivalent and x having a different value from that in the material of said first sensor, whereby the array can distinguish between chlorofluorocarbon, ammonia, and/or organic vapour.
20. An array according to Claim 19, characterised in that said first sensor is of CrNbO..
21. An array according to Claim 18, in which said first sensor is a sensor according to Claim 1 in which the sensing element is of material (iv) , or according to Claim 19 or Claim 20, characterised in that, respectively, the said further sensor or another said further sensor has a sensing element of SnO .
22. .An array according to Claim 18, characterised in that said first sensor is a sensor according to Claim 11, for detection of organic vapours.
23. An array according to Claim 18, characterised in that said first sensor is a sensor according to Claim l in which the sensing element is of material (ix) , at least one second sensor being a sensor responsive to reactive and/or flammable gases but substantially non- responsive to CO at low concentrations to which said first sensor shows a significant response.
24. An array according to Claim 23, characterised in that the said second sensor is a sensor according to Claim 1 in which the sensing element is of material (iv) or material (viii) , for detection of low CO concentrations.
25. An array according to Claim 24, characterised in that the or a said second sensor is a sensor according to Claim 11.
26. An array according to any one of Claims 23 to 25, characterised in that it further includes a humidity sensor arranged for mitigating effects of relative humidity on said first sensor.
27. A method of making an element for a sensor according to any one of Claims l to 17, characterised by the step of adjusting the sintering temperature to control the microstructure, and therefore the selectivity, of the sensing element.
28. A method of making a sensor element according to Claim 1 of material (iv) , characterised by the pretreatment of the sensor element material by exposure to an atmosphere containing H S, so as to increase the amplitude and speed of the response of the sensor element to the presence of H S.
29. A method according to Claim 28, characterised in that the pretreatment step comprises exposing the material to H S in a concentration of 10 parts per million for between 1 and 10 minutes at a temperature greater than 200°C and less than 600°C.
30. A method of detecting at least one gas or vapour, constituting a target gas, characterised by the use of at least one sensor according to any of Claims 1 to 17, or an array according to any of Claims 18 to 22, to produce an electrical resistance signal representing the amount of target gas or gases present.
31. A method according to Claim 30 for measuring hydrocarbons in motor vehicle exhaust gas, characterised by the use of at least one sensor according to Claim 1 in which the sensing element is of a material selected from materials (i) to (iv) , or according to any one of Claims 2 to 6.
32. A method according to Claim 30 using a sensor according to Claim 1 or Claim 6, the sensor element being of material (iv) , characterised in that the sensor detects H S in an aerobic or anaerobic atmosphere, or organic vapours, or SO , or CO, or hydrocarbons other than methane in the presence of methane and/or hydrogen.
33. A method according to Claim 32 when used for the detection of CO leakage from a gas-fired appliance.
34. A method according to Claim 30 using a sensor according to Claim 11 for detection of organic vapours.
35. A method according to Claim 34 when used for detecting CO.
36. A method according to Claim 30 for measurement of oxygen partial pressure, characterised by the use of a sensor according to Claim 1 in which the sensing element is of material (v) , or of material (x) , the method including applying heating to maintain the sensor at a constant temperature.
37. A method according to Claim 30 for detecting the presence of chlorofluorocarbon, characterised by the use of an array according to Claim 19 or Claim 20.
38. A method according to Claim 37, characterised in that the array is an array according to Claim 21, so as, in addition, to detect the presence of ammonia and/or solvent vapour.
39. A method according to Claim 30 for monitoring small concentrations of CO in at least partly closed-circuit atmospheres, characterised by the use of an array according to any one of Claims 23 to 26.
Priority Applications (12)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU69765/94A AU6976594A (en) | 1993-06-18 | 1994-06-20 | Semiconducting oxide gas sensors and materials therefor |
| GB9503164A GB2285689A (en) | 1993-06-18 | 1994-06-20 | Semiconducting oxide gas sensors and materials therefor |
| JP7502565A JPH08500447A (en) | 1993-06-18 | 1994-06-20 | Oxide semiconductor gas sensor and its substance |
| EP94918449A EP0656111B1 (en) | 1993-06-18 | 1994-06-20 | Use of semiconducting oxide gas sensors |
| DE69422892T DE69422892T2 (en) | 1993-06-18 | 1994-06-20 | USE OF SEMICONDUCTOR GAS SENSORS |
| CA002142696A CA2142696C (en) | 1993-06-18 | 1994-06-20 | Semiconducting oxide gas sensors and materials therefor |
| GBGB9501461.9A GB9501461D0 (en) | 1994-06-20 | 1995-01-25 | Detection of ozone |
| GB9626807A GB2305730B (en) | 1994-06-20 | 1995-06-20 | Resistive gas sensing, especially for detection of ozone |
| CA002193646A CA2193646C (en) | 1994-06-20 | 1995-06-20 | Resistive gas sensing, especially for detection of ozone |
| PCT/GB1995/001452 WO1995035495A1 (en) | 1994-06-20 | 1995-06-20 | Resistive gas sensing, especially for detection of ozone |
| JP8501838A JPH10501623A (en) | 1994-06-20 | 1995-06-20 | Resistive gas detection especially useful for ozone detection |
| EP95922626A EP0767905B1 (en) | 1994-06-20 | 1995-06-20 | Resistive gas sensing, especially for detection of ozone |
Applications Claiming Priority (8)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9312619.1 | 1993-06-18 | ||
| GB939312619A GB9312619D0 (en) | 1993-06-18 | 1993-06-18 | Semiconducting oxide gas sensor materials |
| GB939321908A GB9321908D0 (en) | 1993-10-23 | 1993-10-23 | Semiconducting oxide gas sensor materials |
| GB9321908.7 | 1993-10-23 | ||
| GB939326148A GB9326148D0 (en) | 1993-12-22 | 1993-12-22 | Oxygen sensors |
| GB9326148.5 | 1993-12-22 | ||
| GB9403211.7 | 1994-02-19 | ||
| GB9403211A GB9403211D0 (en) | 1994-02-19 | 1994-02-19 | Semiconducting oxide gas sensor materials |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| WO1995000836A1 WO1995000836A1 (en) | 1995-01-05 |
| WO1995000836B1 true WO1995000836B1 (en) | 1995-02-09 |
Family
ID=27451035
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/GB1994/001327 WO1995000836A1 (en) | 1993-06-18 | 1994-06-20 | Semiconducting oxide gas sensors and materials therefor |
Country Status (7)
| Country | Link |
|---|---|
| EP (2) | EP0940673B1 (en) |
| JP (2) | JPH08500447A (en) |
| AU (1) | AU6976594A (en) |
| CA (1) | CA2142696C (en) |
| DE (2) | DE69422892T2 (en) |
| GB (1) | GB2285689A (en) |
| WO (1) | WO1995000836A1 (en) |
Families Citing this family (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3299623B2 (en) * | 1994-03-23 | 2002-07-08 | 能美防災株式会社 | Odor pressure measurement method, odor pressure standardization method, odor detection device, and fire detection device |
| GB9526393D0 (en) * | 1995-12-22 | 1996-02-21 | Capteur Sensors & Analysers | Gas sensing |
| WO1997028441A1 (en) * | 1996-01-30 | 1997-08-07 | Capteur Sensors & Analysers Ltd. | Detection of gases |
| US5736104A (en) * | 1996-03-27 | 1998-04-07 | Motorola Inc. | Transition metal oxide based calorimetric non-methane hydrocarbon sensor and method |
| DE19623212A1 (en) * | 1996-06-11 | 1997-12-18 | Bosch Gmbh Robert | Sensor for determining the concentration of oxidizable components in a gas mixture |
| EP0851222A1 (en) * | 1996-12-31 | 1998-07-01 | Corning Incorporated | Metal oxide semiconductor catalyst hydrocarbon sensor |
| DE19856369C2 (en) * | 1998-12-07 | 2000-12-07 | Siemens Ag | Resistive gas sensor and method for its production |
| GB0011704D0 (en) * | 2000-05-15 | 2000-07-05 | Capteur Sensors And Analysers | Gas sensors with improved resistance to humidity interference |
| CA2480090C (en) * | 2002-04-05 | 2011-07-12 | E.I. Du Pont De Nemours And Company | Method and apparatus for controlling a gas-emitting process and related devices |
| GB0223350D0 (en) | 2002-10-08 | 2002-11-13 | City Tech | Flue gas sensors |
| JP2007155529A (en) * | 2005-12-06 | 2007-06-21 | Ngk Spark Plug Co Ltd | Ammonia gas sensor and its manufacturing method |
| WO2007117290A2 (en) * | 2005-12-12 | 2007-10-18 | Nextech Materials, Ltd. | Ceramic h2s sensor |
| ES1063777Y (en) | 2006-09-18 | 2007-03-01 | Uriarte Genaro Arana | PERFECTED CONVECTION RADIATOR |
| JP2010507088A (en) | 2006-10-19 | 2010-03-04 | ソシエテ ド シミ イノルガニク エ オルガニク アン アブレジェ “ソシノール” | Combustion gas sensor |
| US8596108B2 (en) | 2007-10-01 | 2013-12-03 | Scott Technologies, Inc. | Gas measuring device and method of operating the same |
| US7827852B2 (en) | 2007-12-20 | 2010-11-09 | General Electric Company | Gas sensor and method of making |
| JP5234925B2 (en) * | 2008-04-03 | 2013-07-10 | 株式会社神戸製鋼所 | Hard film, method for forming the same, and hard film coated member |
| US9759676B2 (en) | 2012-09-03 | 2017-09-12 | Kake Educational Institution | Gas sensor array, gas analysis method, and gas analysis system |
| KR101434327B1 (en) * | 2013-03-29 | 2014-08-27 | (주)알에프트론 | Transparent compound semiconductor and p-type Doping Method thereof |
| US10120097B2 (en) | 2016-04-05 | 2018-11-06 | Baker Hughes Incorporated | Methods and apparatus for measuring hydrogen sulfide in downhole fluids |
| KR102567482B1 (en) * | 2021-01-26 | 2023-08-17 | 한국과학기술연구원 | Development of highly senstive ammonia gas sensor and ammonia gas sensor system using graphene doped with tin oxide and nickel oxide nanoparticles, and a method for manufacturing the same |
| KR102670896B1 (en) * | 2021-01-29 | 2024-06-03 | 한국세라믹기술원 | Fluorescent composition for hydrogen sulfide gas sensor |
| CN114216936B (en) * | 2021-12-20 | 2022-12-09 | 湖北工业大学 | Preparation method and application of cubic phase molybdenum carbide nanowire gas sensor |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4007435A (en) * | 1973-07-30 | 1977-02-08 | Tien Tseng Ying | Sensor device and method of manufacturing same |
| JPS5766347A (en) * | 1980-10-09 | 1982-04-22 | Hitachi Ltd | Detector for mixture gas |
| DE3213286C2 (en) * | 1982-04-08 | 1986-01-23 | Hitachi, Ltd., Tokio/Tokyo | Gas detection device |
| GB8329004D0 (en) * | 1983-10-31 | 1983-11-30 | Atomic Energy Authority Uk | Sensors |
-
1994
- 1994-06-20 DE DE69422892T patent/DE69422892T2/en not_active Expired - Fee Related
- 1994-06-20 DE DE69435203T patent/DE69435203D1/en not_active Expired - Lifetime
- 1994-06-20 GB GB9503164A patent/GB2285689A/en not_active Withdrawn
- 1994-06-20 EP EP99201929A patent/EP0940673B1/en not_active Expired - Lifetime
- 1994-06-20 AU AU69765/94A patent/AU6976594A/en not_active Abandoned
- 1994-06-20 EP EP94918449A patent/EP0656111B1/en not_active Expired - Lifetime
- 1994-06-20 WO PCT/GB1994/001327 patent/WO1995000836A1/en active IP Right Grant
- 1994-06-20 CA CA002142696A patent/CA2142696C/en not_active Expired - Fee Related
- 1994-06-20 JP JP7502565A patent/JPH08500447A/en active Pending
-
2003
- 2003-04-22 JP JP2003117555A patent/JP3626485B2/en not_active Expired - Fee Related
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