MATERIALS AND SENSORS FOR DETECTING GASEOUS AGENTS

• US 20160187280A1
• Filed: 12/30/2014
• Published: 06/30/2016
• Est. Priority Date: 12/30/2014
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (General Electric Company)
• Original Assignee: General Electric Company
• Inventors: Potyralio, Radislav Alexandrovich, Bartling, Brandon, Tang, Zhexiong, Nagraj, Nandini, Bromberg, Vadim
• Granted Patent: US 9,678,030 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01N 27/125 Composition of the body, e.g. the composition of its sensitive layer
• CPC Class Codes: G01N 27/227 Sensors changing capacitance upon adsorption or absorption of fluid components, e.g. electrolyte-insulator-semiconductor sensors, MOS capacitors G01N27/225 takes precedence
• CPC Class Codes: G01N 27/228 Circuits therefor measuring capacitance per se G01R27/26
• CPC Class Codes: G01N 31/10 using catalysis
• CPC Class Codes: G01N 33/0036 specially adapted to detect a particular component physical analysis of gaseous biological material G01N33/497

Abstract

A sensor for detecting gaseous agents has a transducer, which includes an electrical resonant circuit that forms an antenna. The sensor further includes a sensing material that is disposed on at least a portion of the transducer. The sensing material is configured to simultaneously exhibit a capacitance response and a resistance response in the presence of a gaseous agent. The sensor may be reversible, battery free, and may require no electrical contact with a sensor reader.

Claims

1. A sensor configured to detect a gaseous agent comprising:

a transducer, wherein the transducer comprises an electrical resonant circuit that forms an antenna; and

a sensing material disposed at least on the portion of the transducer, wherein the sensing material is configured to simultaneously exhibit a capacitance response and a resistance response when exposed to a gaseous agent.

2. The sensor of claim 1, wherein the gaseous agent is a sterilization agent, a fumigation agent, or a decontamination agent.

3. The sensor of claim 1, wherein the sensing material has a reversible response when exposed to the gaseous agent.

4. The sensor of claim 1, wherein the sensing material is configured to measure a concentration of the gaseous agent as a dosimeter.

5. The sensor of claim 1, wherein the sensing material comprises metal nanoparticles coated at least in part with an organic layer.

6. The sensor of claim 1, wherein the sensing material comprises a semiconducting metal oxide and a noble metal catalyst deposited on the semiconducting metal oxide.

7. The sensor of claim 6, wherein the noble metal catalyst is any one of the following:

platinum, palladium, gold, silver, aluminum, copper, iron, nickel, ruthenium, or any combination thereof, and wherein the semiconducting metal oxide is any one of the following;

In₂O₃, ZnO, WO₃, SnO₂, TiO₂, Fe₂O₃, Ga₂O₃ and Sb₂O₃ or any other semiconducting metal oxide, or a combination of one or more metals including In₂O₃ with SnO₂, In₂O₃ with ZnO, SnO₂ with ZnO, or any other combination of metals.

8. The sensor of claim 6, wherein the noble metal catalyst is deposited on the semiconducting metal oxide using wetness impregnation or in-situ synthesis.

9. The sensor of claim 6, wherein the weight percentage of noble metal catalyst to semiconducting metal oxide is in the range of 0.01% to 1%.

10. The sensor of claim 1, wherein the sensor is configured to operate at an ambient temperature.

11. The sensor of claim 10, wherein the ambient temperature is between −

40 degrees Centigrade to 1000 degrees Centigrade.

12. The sensor of claim 1, wherein the transducer is a passive RFID platform transducer, an inductor-capacitor-resistor (LCR) resonator, a thickness shear mode resonator, an interdigital electrode structure, or an electrode structure.

13. The sensor of claim 1, wherein the sensing material is disposed on a complementary sensing region of the sensor.

14. A sensor configured to detect a gaseous agent, the sensor comprising:

a transducer, wherein the transducer comprises an antenna;

a sensing material disposed on the transducer, wherein the sensing material comprises a semiconducting metal oxide and a noble metal catalyst deposited on the semiconducting metal oxide; and

wherein the antenna is configured to emit an electric field to probe a response of the sensing material when exposed to a gaseous agent.

15. The sensor of claim 14, wherein the sensing material further comprises a tunable polymer additive, and wherein the semiconducting metal oxide is a semiconducting mixed metal oxide.

16. The sensor of claim 15, wherein the sensing material comprises between 1% and 80% of the tunable polymer additive.

17. The sensor of claim 14, wherein the response of the sensing material is both a change in a capacitance and a change in a resistance.

18. The sensor of claim 14, wherein the sensing material is disposed on a complementary sensing region of the sensor.

24. The method of claim 18, wherein disposing the antenna on the transducer is performed using printing.

19. A method for preparing a sensor configured to detect a gaseous agent comprising:

assembling a transducer by disposing an antenna on a substrate;

doping a noble metal catalyst to a semiconducting metal oxide to form a metal oxide powder;

mixing the metal oxide powder with an aqueous solution of a polymer matrix to form a stable metal oxide suspension;

depositing the metal oxide suspension on the transducer; and

drying the metal oxide suspension to form a sensing material.

20. The method of claim 19, wherein the noble metal catalyst is any one of the following:

platinum, palladium, gold, silver, aluminum, copper, iron, nickel, ruthenium, or any combination thereof.

21. The method of claim 19, wherein the semiconducting metal oxide is any one of the following:

In₂O₃, ZnO, WO₃, SnO₂, TiO₂, Fe₂O₃, Ga₂O₃ and Sb₂O₃ or any other semiconducting metal oxide, or a combination of one or more metals including In₂O₃ with SnO₂, In₂O₃ with ZnO, SnO₂ with ZnO, or any other combination of metals.

22. The method of claim 19, wherein the polymer matrix is formed by dissolving a polymer additive in water, ethanol, isopropanol, hexane, toluene, 1-Methyl-2-Pyrrolidinone, or any combination thereof.

23. The method of claim 19, wherein the polymer matrix is any of the following:

polyvinlyldene fluoride (PVDF), polyvinyl alcohol (PVO), polyacrylic acid (PAA), chloro metal acid, or any combination thereof.

25. A method for detecting a concentration of a gaseous agent comprising:

exposing a sensing material to a gaseous agent, wherein the sensing material comprises a first component and a second component, and wherein the first component and the second component are deposited on a surface of a sensing coil;

oxidizing or reducing the first component and/or the second component;

measuring a capacitance response and a resistance response of the sensing material over a frequency range; and

conducting analysis on the capacitance response and the resistance response of the sensing material to detect a concentration of the gaseous agent.

26. The method of claim 25, wherein the sensing material comprises metal nanoparticles coated at least in part with an organic layer.

27. The method of claim 25, wherein the analysis is univariate or multivariate.

28. The method of claim 25, wherein the first component is a semiconducting metal oxide and the second component is a noble metal catalyst, and wherein the noble metal catalyst is deposited on the surface of the semiconducting metal oxide.

29. The method of claim 25, wherein the analysis facilitates for self-correction against fluctuations in ambient temperature.

30. The method of claim 25, wherein the sensing material has a reversible response to the gaseous agent.