Metal and metal oxide co-functionalized single-walled carbon nanotubes for high performance gas sensors

Patent metadata

Field	Value
Publication number	US-9304094-B2
Application number	US-201113111452-A
Country	US
Kind code	B2
Filing date	May 19, 2011
Priority date	May 19, 2010
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A method of co-functionalizing single-walled carbon nanotubes for gas sensors, which includes the steps of: fabricating single-walled carbon nanotube interconnects; synthesizing tin oxide onto the single-walled carbon nanotube interconnects; and synthesizing metal nanoparticles onto the tin oxide coated single-walled carbon nanotube interconnects.

First claim

What is claimed is:

1. A method of co-functionalizing single-walled carbon nanotube interconnects for gas sensors, the method comprising:
fabricating by alignment single-walled carbon nanotube interconnects;
synthesizing discrete tin oxide nanocrystallites onto a surface of the single-walled carbon nanotube interconnects by electrodeposition; and
synthesizing metal nanoparticles onto the discrete tin oxide nanocrystallites and the surface of the single-walled carbon nanotube interconnects by electrodeposition, and
wherein an overall sensitivity of the gas sensor is enhanced compared to other single-walled carbon nanotube gas sensors.

2. The method of claim 1 , comprising:
fabricating the single-walled carbon nanotube interconnects across a gap between a pair of electrodes.

3. The method of claim 2 , further comprising:
controlling the number of single-walled carbon nanotube interconnects by adjusting a concentration of single-walled carbon nanotube in a solution.

4. The method of claim 2 , further comprising:
controlling the number of single-walled carbon nanotube interconnects by adjusting an alignment time.

5. The method of claim 3 , wherein the aligning of the single-walled carbon nanotube interconnects comprises:
an AC dielectrophoresis process.

6. The method of claim 1 , wherein the tin oxide nanocrystallites are synthesized onto the single-walled carbon nanotube interconnects from an electrolyte solution comprised of NaNO 3 , HNO 3 , SnCl 2 .5H 2 O and/or other tin ion precursors.

7. The method of claim 1 , wherein the metal nanoparticles are palladium (Pd).

8. The method of claim 1 , wherein the metal nanoparticles are platinum (Pt).

9. The method of claim 1 , wherein the metal nanoparticles are gold (Au).

10. The method of claim 1 , further comprising:
fabricating a plurality of said co-functionalizing single-walled carbon nanotube interconnects, which form a plurality of gas sensors, and wherein the plurality of gas sensors are wire-bonded and each sensor is connected in series with a load resistor.

11. The method of claim 1 , wherein the gas sensors are co-functionalized for sensing at room temperature.

12. A method of co-functionalizing single-walled carbon nanotube interconnects for gas sensors, the method comprising:
fabricating by alignment single-walled carbon nanotube interconnects across a gap between a pair of electrodes;
templating discrete tin oxide nanocrystallites onto a surface of the single-walled carbon nanotube interconnects by electrodeposition; and
depositing metal nanoparticles onto the discrete tin oxide nanocrystallites and the surface of the single-walled carbon nanotube interconnects by electrodeposition, and
wherein an overall sensitivity of the gas sensor is enhanced compared to other single-walled carbon nanotube gas sensors.

13. The method of claim 12 , further comprising:
controlling the number of single-walled carbon nanotube interconnects by adjusting a concentration of single-walled carbon nanotube in a solution.

14. The method of claim 12 , further comprising:
controlling the number of single-walled carbon nanotube interconnects by adjusting an alignment time.

15. The method of claim 14 , wherein the aligning of the single-walled carbon nanotube interconnects comprises:
an AC dielectrophoresis process.

16. The method of claim 12 , comprising:
an electrolyte solution comprised of NaNO 3 , HNO 3 , SnCl 2 .5H 2 O and/or other tin ion precursors which is templated onto the single-walled carbon nanotube interconnects as the discrete tin oxide nanocrystallites.

17. The method of claim 12 , wherein the metal nanoparticles are palladium (Pd).

18. The method of claim 12 , wherein the metal nanoparticles are platinum (Pt).

19. The method of claim 12 , wherein the metal nanoparticles are gold (Au).

20. The method of claim 12 , further comprising:
fabricating a plurality of said co-functionalizing single-walled carbon nanotube interconnects, which form a plurality of gas sensors, and wherein the plurality of gas sensors are wire-bonded and each sensor is connected in series with a load resistor.

21. The method of claim 12 , wherein the gas sensors are co-functionalized for sensing at room temperature.

Assignees

• Myung Nosang Vincent
• Mubeen Syed
• Mulchandani Ashok
• Deshusses Marc Arnold
• Univ California

Inventors

• Myung Nosang Vincent
• Mubeen Syed
• Mulchandani Ashok
• Deshusses Marc Arnold

Classifications

• G01N27/127 Primary

  comprising nanoparticles · CPC title

• B82Y15/00

  Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors · CPC title

• G01N27/4074 Primary

  for detection of gases other than oxygen · CPC title

• G01N27/4075

  Composition or fabrication of the electrodes and coatings thereon, e.g. catalysts · CPC title

• G01N27/417

  using cells {, i.e. more than one cell} and probes with solid electrolytes · CPC title