Metal nanoparticle-decorated nanotubes for gas sensing

Patent metadata

Field	Value
Publication number	US-2020378914-A1
Application number	US-202016996239-A
Country	US
Kind code	A1
Filing date	Aug 18, 2020
Priority date	Apr 28, 2017
Publication date	Dec 3, 2020
Grant date	—

Abstract

Disclosed herein are embodiments of compositions for gas sensing and sensors utilizing the same. In one embodiment, a composition comprises carbon nanotubes and polymer-coated metal nanoparticles bound to the carbon nanotubes.

First claim

What is claimed is:

1 . A composition comprising:
carbon nanotubes having an average degree of functionalization with carboxylic acid groups and/or hydroxyl groups that is less than 3 percent by weight (wt %) based on a total weight of the carbon nanotubes; and polymer-coated metal nanoparticles bound to the carbon nanotubes.

2 . The composition of claim 1 , wherein the polymer-coated metal nanoparticles are non-covalently bound to the carbon nanotubes.

3 . The composition of claim 1 , wherein the carbon nanotubes are substantially free of carboxylic acid functional groups and hydroxyl functional groups.

4 . The composition of claim 1 , wherein the carbon nanotubes comprise single-walled carbon nanotubes or multi-wall carbon nanotubes.

5 . The composition of claim 1 , wherein the polymer-coated metal nanoparticles each comprise a metallic core and a polymer layer covalently bound to the metallic core.

6 . The composition of claim 5 , wherein the polymer layer comprises a hydrophobic polymer.

7 . The composition of claim 5 , wherein the metallic core comprises a metal selected from a group consisting of palladium, iridium, rhodium, platinum, and gold.

8 . The composition of claim 5 , wherein the polymer layer comprises poly(vinylpyrrolidinone), and wherein the metallic core comprises palladium.

9 . The composition of claim 1 , wherein the composition is dispersed in an organic solvent.

10 . The composition of claim 1 , wherein the polymer-coated-metal nanoparticles are coated with a hydrophobic polymer layer.

11 . The composition of claim 1 , wherein the carbon nanotubes are substantially free of carboxylic acid functional groups and hydroxyl functional groups.

12 . The composition of claim 1 , wherein the carbon nanotubes comprise single-walled carbon nanotubes or multi-wall carbon nanotubes.

13 . The composition of claim 1 , wherein the polymer-coated metal nanoparticles each comprise a metallic core, and wherein the polymer layer is covalently bound to the metallic core.

14 . A method of producing metal nanoparticle-decorated carbon nanotubes, the method comprising:
forming a reaction mixture by combining a first solution with a second solution, wherein the first solution comprises polymer-coated metal nanoparticles comprising metallic nanoparticles coated with a polymer, and wherein the second solution comprises carbon nanotubes; and heating the reaction mixture to a temperature greater than a glass transition temperature of the polymer for a time sufficient to cause the polymer-coated metal nanoparticles to bind to the carbon nanotubes forming the metal nanoparticle-decorated carbon nanotubes.

15 . The method of claim 14 , wherein the polymer-coated metal nanoparticles are fully-formed prior to forming the reaction mixture.

16 . The method of claim 15 , wherein the polymer-coated metal nanoparticles are non-covalently bound to the carbon nanotubes.

17 . The method of claim 14 , wherein an average degree of functionalization of the carbon nanotubes with carboxylic acid groups and/or hydroxyl groups is less than 3 wt % based on a total weight of the carbon nanotubes.

18 . The method of claim 14 , further comprising:
dispersing the metal nanoparticle-decorated carbon nanotubes in a non-aqueous solvent-based ink.

19 . The method of claim 14 , wherein the polymer-coated-metal nanoparticles are coated with a hydrophobic polymer layer.

20 . The method of claim 14 , wherein the carbon nanotubes are substantially free of carboxylic acid functional groups and hydroxyl functional groups.

Assignees

• Palo Alto Res Ct Inc

Inventors

• Iftime Gabriel
• Smith Clinton
• Schwartz David Eric
• Zhang Yong
• Vedharathinam Vedasri

Classifications

• B22F1/102

  Metallic powder coated with organic material · CPC title

• B01J20/205 Primary

  Carbon nanostructures, e.g. nanotubes, nanohorns, nanocones, nanoballs (carbon nanotubes per se C01B32/15) · CPC title

• G01N27/04 Primary

  by investigating resistance · CPC title

• G01N33/0009

  General constructional details of gas analysers, e.g. portable test equipment (devices for withdrawing samples in the gaseous state G01N1/22) · CPC title

• B01J20/0225

  Compounds of Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt · CPC title