High-density carbon nanotube aggregate and method of producing high-density carbon nanotube aggregate

• US 10,640,380 B2
• Filed: 02/24/2016
• Issued: 05/05/2020
• Est. Priority Date: 02/27/2015
• Status: Active Grant

• Current Assignee: Hitachi Zosen Corporation
• Original Assignee: Hitachi Zosen Corporation
• Inventors: Maruyama, Hiroyuki
• Primary Examiner(s): Usyatinsky, Alexander
• Application Number:
  US15/553,382
• Publication Number:
  US 20180118571A1
• Time in Patent Office: 1,532 Days
• CPC Class Codes: B01J 20/205 Carbon nanostructures, e.g. nanotubes, nanohorns, nanocones, nanoballs carbon nanotubes per se C01B32/15
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01B 32/05 Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
• CPC Class Codes: C01B 32/162 characterised by catalysts
• CPC Class Codes: C01B 32/17 Purification
• CPC Class Codes: C01B 32/21 After-treatment
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer

Abstract

A method of producing a high-density carbon nanotube aggregate includes the steps of: preparing a carbon nanotube array including a plurality of carbon nanotubes aligned on a substrate and oriented vertically to the substrate; and heating the carbon nanotube array to 2,600° C. or higher.

Claims

1. A method of producing a high-density carbon nanotube aggregate comprising the steps of:

preparing a carbon nanotube array including a plurality of carbon nanotubes aligned on a substrate and oriented vertically to the substrate; and

heating the carbon nanotube aggregate to 2,800°

C. or higher in an inert gas atmosphere, for 10 minutes or more and 5 hours or less,

wherein an average bulk density of the high-density carbon nanotube aggregate is from 100 mg/cm³ to 200 mg/cm³; and

an average G/D ratio of the high-density carbon nanotube aggregate is from 2 to 30,

wherein G refers to a first spectral intensity of a peak called the G band, and D refers to a second spectral intensity of another peak called the D band in the Raman spectrum of the carbon nanotube.

2. The method of producing the high-density carbon nanotube aggregate of claim 1, wherein heating the carbon nanotube array comprises:

removing the carbon nanotube array from the substrate; and

then heating the carbon nanotube array.

3. The method of producing the high-density carbon nanotube aggregate of claim 1, wherein heating the carbon nanotube array comprises heating the carbon nanotube array in a no-load state.

4. The method of producing the high-density carbon nanotube aggregate of claim 1 further comprising:

cooling the carbon nanotube array to 2,000°

C. or lower after heating the carbon nanotube array,

wherein the steps of heating the carbon nanotube array and cooling the carbon nanotube array are repeated sequentially.

5. The method of producing the high-density carbon nanotube aggregate of claim 1, further comprising supplying a liquid to the carbon nanotube array after heating the carbon nanotube array.

6. A high-density carbon nanotube aggregate produced by a method of producing a high-density carbon nanotube aggregate of comprising the steps of:

preparing a carbon nanotube array including a plurality of carbon nanotubes aligned on a substrate and oriented vertically to the substrate; and

heating the carbon nanotube array to 2,800°

C. or higher in an inert gas atmosphere for 10 minutes or more and 5 hours or less,

wherein an average bulk density of the plurality of carbon nanotubes is from 100 mg/cm³ to 200 mg/cm³; and

an average G/D ratio of the high-density carbon nanotube aggregate is from 2 to 30, wherein G refers to a first spectral intensity of a peak called the G band, and D refers to a second spectral intensity of another peak called the D band in the Raman spectrum of the carbon nanotube.