Production apparatus for carbon nanohorn aggregate

Patent metadata

Field	Value
Publication number	US-11485641-B2
Application number	US-201716636180-A
Country	US
Kind code	B2
Filing date	Aug 4, 2017
Priority date	Aug 4, 2017
Publication date	Nov 1, 2022
Grant date	Nov 1, 2022

Abstract

In order to provide an apparatus for industrially producing a fibrous carbon nanohorn aggregate (CNB), the apparatus comprises: a target holding unit holding a carbon target in sheet form containing a metal catalyst such as Fe; a light source irradiating a laser beam on a surface of the carbon target; a movement unit moving one of the target held by the target holding unit and the light source relative to the other to move the irradiation position of the laser beam on the surface of the target; a production chamber configured to irradiate the carbon target with the laser beam in an atmosphere of non-oxidizing gas to produce a product including the fibrous carbon nanohorn aggregate; a collection mechanism collecting carbon vapor evaporated from the target by irradiation of the laser beam to collect nanocarbon including the fibrous carbon nanohorn aggregate; and a control unit controlling an operation of the movement unit or the light source so that the power density of the laser beam irradiated to the surface of the carbon target is substantially constant, and the irradiation position of the laser beam is moved to a region adjacent to a region previously irradiated by the laser beam, an interval being formed therebetween that is equal to or larger than the width of an altered region formed on the periphery of the region irradiated by the laser beam.

First claim

The invention claimed is:

1. A production apparatus for manufacturing carbon nanohorn aggregates including a fibrous carbon nanohorn aggregate, the apparatus comprising:
a production chamber configured to receive a laser beam for irradiating a carbon target in sheet form containing a metal catalyst selected from a single body of Fe, Ni, Co or a mixture of these two or three of them in and atmosphere of non-oxidizing gas to produce a product including the fibrous carbon nanohorn aggregate;
a target holding unit configured to hold the carbon target inside the production chamber;
a light source configured to emit the laser beam onto a surface of the carbon target;
a laser focal position adjustment mechanism configured to introduce the laser beam emitted from the light source into the production chamber;
a movement unit configured to move the carbon target held by the target holding unit for moving the laser beam irradiation position on the surface of the carbon target;
a collection chamber connected to the production chamber via a transfer pipe and configured to collect carbon vapor vaporized from the carbon target by irradiation with the laser beam;
a collection mechanism configured to collect product including the fibrous carbon nanohorn aggregate in the collecting chamber;
a gas inlet configured to introduce the gas that makes the generation chamber a non-oxidizing gas atmosphere; and
an exhaust port configured to exhaust the ambient gas in the collection chamber; and
a control unit configured to control an operation of the movement unit or the light source so that the power density of the laser beam irradiated to the surface of the carbon target is substantially constant, and the irradiation position of the laser beam is moved to a region adjacent to a region previously irradiated by the laser beam, an interval being formed therebetween that is equal to or larger than the width of an altered region formed on the periphery of the region irradiated by the laser beam;
wherein the gas inlet is located adjacent to the laser focal position adjustment mechanism, and
the control unit is configured to match the gas flow rate introduced from the gas inlet to the gas flow rate exhausted from the exhaust port to provide a constant gas flow rate in the production chamber.

2. The production apparatus according to claim 1 , wherein the movement unit is configured to move the irradiation position of the laser beam while keeping the irradiation angle of the laser beam at the irradiation position on the surface of the carbon target substantially constant.

3. The production apparatus according to claim 1 , wherein the movement unit is configured to move the irradiation position of the laser beam from one end of the target to the other end in a row, and move the laser beam to the next row at intervals equal to or larger than the width of the altered region formed around the irradiation region formed by the irradiation.

4. The production apparatus according to claim 1 , wherein the carbon target is a single sheet-like target, and the movement unit is controlled by the control unit so as to move the target in a spiral shape on the target by rotating and driving the target and moving the irradiation position from the outer periphery of the target toward the inner portion or in the opposite direction.

5. The production apparatus according to claim 1 , wherein the moving speed of the laser beam irradiation position is in the range of 3 cm/min to 50 cm/min.

6. The production apparatus according to claim 5 , wherein the output of the laser beam is in the range of 2.0 kW to 10 kW.

7. The production apparatus according to claim 1 , wherein the collection mechanism comprises a collection container containing a liquid inert to the carbon nanohorn aggregate, and suspends and recovers the carbon nanohorn aggregate produced in the liquid.

8. The production apparatus according to claim 1 , wherein the catalyst is Fe.

Assignees

• Nec Corp

Inventors

• Yuge Ryota

Classifications

• B01J2219/0879

  Solid · CPC title

• C01P2004/04

  obtained by TEM, STEM, STM or AFM · CPC title

• C23C14/24

  Vacuum evaporation · CPC title

• C01B32/18 Primary

  Nanoonions; Nanoscrolls; Nanohorns; Nanocones; Nanowalls · CPC title

• B01J19/121 Primary

  Coherent waves, e.g. laser beams (lasers per se H01S3/00) · CPC title