Nanoparticle-Based Gas Sensors and Methods of Using the Same

Patent metadata

Field	Value
Publication number	US-2018024089-A1
Application number	US-201715703752-A
Country	US
Kind code	A1
Filing date	Sep 13, 2017
Priority date	Oct 5, 2012
Publication date	Jan 25, 2018
Grant date	—

Abstract

Gas sensors are provided. The gas sensors include a gas sensing element having metal oxide nanoparticles and a thin-film heating element. Systems that include the gas sensors, as well as methods of using the gas sensors, are also provided. Embodiments of the present disclosure find use in a variety of different applications, including detecting whether an analyte is present in a gaseous sample.

First claim

1 . A gas sensor comprising:
a gas sensing element comprising metal oxide nanoparticles; a thin-film heating element; and a membrane comprising an insulation material, wherein the insulation material is between the membrane and the thin-film heating element.

2 . The gas sensor of claim 1 , wherein the gas sensing element comprises a first electrode and a second electrode with the metal oxide nanoparticles disposed between the first electrode and the second electrode.

3 . The gas sensor of claim 1 , wherein the metal oxide nanoparticles comprise tungsten oxide nanoparticles and the gas sensor is configured to detect hydrogen sulfide.

4 . The gas sensor of claim 3 , wherein the metal oxide nanoparticles have an average diameter of 100 nm or less.

5 . The gas sensor of claim 1 , wherein the thin-film heating element comprises polysilicon.

6 . The gas sensor of claim 1 , further comprising an insulation layer between the gas sensing element and the thin-film heating element.

7 . The gas sensor of claim 6 , wherein the insulation layer comprises silicon nitride.

8 . The gas sensor of claim 1 , wherein the gas sensor is configured to have a thermal efficiency ranging from 30° C./mW to 200° C./mW.

9 . The gas sensor of claim 1 , wherein the gas sensor is configured to have a limit of detection of 1 ppm or less.

10 . A gas sensor system comprising:
one or more gas sensors, wherein each gas sensor comprises:
gas sensing element comprising metal oxide nanoparticles;
a thin-film heating element; and
a membrane comprising an insulation material, wherein the insulation material is between the membrane and the thin-film heating element.

11 . The gas sensor system of claim 10 , wherein the gas sensor system comprises an array of 6 or more gas sensors.

12 . (canceled)

13 . The gas sensor system of claim 11 , wherein the array has a length of 3 mm or less and a width of 3 mm or less.

14 . The gas sensor system of claim 10 , further comprising a controller configured to repeatedly activate and deactivate the thin-film heating element over a period of time.

15 . The gas sensor system of claim 14 , wherein the controller is configured to activate the thin-film heating element with a duty cycle of 20% or less.

16 . The gas sensor system of claim 14 , wherein the controller is configured to activate the thin-film heating element with a frequency of 0.1 Hz or more.

17 . A method of detecting whether an analyte is present in a gaseous sample, the method comprising:
contacting a gaseous sample to a gas sensor to produce a signal, the gas sensor comprising:
a gas sensing element comprising metal oxide nanoparticles;
a thin-film heating element; and
a membrane comprising an insulation material, wherein the insulation material is between the membrane and the thin-film heating element; and
analyzing the signal to determine whether the analyte is present in the gaseous sample.

18 . The method of claim 17 , further comprising heating the gas sensing element with the thin-film heating element during the contacting.

19 . The method of claim 18 , wherein the heating comprises repeatedly activating and deactivating the thin-film heating element over a period of time.

20 . The method of claim 17 , further comprising determining the concentration of the analyte in the gaseous sample based on the signal.

21 . The method of claim 20 , further comprising activating an alarm if the concentration of the analyte is greater than a threshold value.

Assignees

• Univ California

Inventors

• Mickelson William
• Zettl Alex K

Classifications

• G01N27/403 Primary

  Cells and electrode assemblies · CPC title

• G01N33/0044 Primary

  Sulphides, e.g. H2S · CPC title

• G01N27/127

  comprising nanoparticles · CPC title