Ultra-long chiral carbon nanotube, method for preparing the same, application thereof, and high-performance photoelectric device

Patent metadata

Field	Value
Publication number	US-11613466-B2
Application number	US-202017131676-A
Country	US
Kind code	B2
Filing date	Dec 22, 2020
Priority date	Dec 25, 2019
Publication date	Mar 28, 2023
Grant date	Mar 28, 2023

Abstract

This disclosure relates to the technical field of carbon nanotubes, provides an ultra-long chiral carbon nanotube and a method for preparing the same. The ultra-long chiral carbon nanotube has a diameter of about 1.5 nm to 5.5 nm and has a length of about 100 mm to 650 mm, the ultra-long chiral carbon nanotube includes a double-walled carbon nanotube and a triple-walled carbon nanotube, and each layer of the ultra-long chiral carbon nanotube is semiconducting and has a helix angle greater than 10°.

First claim

What is claimed is:

1. An ultra-long chiral carbon nanotube, comprising:
at least one of a double-walled carbon nanotube and a triple-walled carbon nanotube, wherein each layer of the ultra-long chiral carbon nanotube is semiconducting and has a helix angle greater than 10°, and
wherein the ultra-long chiral carbon nanotube has a diameter between about 1.5 nm and 5.5 nm and has a length between about 100 mm and 650 mm.

2. The ultra-long chiral carbon nanotube of claim 1 , wherein the ultra-long chiral carbon nanotube has a minimum band gap distribution of 0.2 eV˜0.45 eV.

3. The ultra-long chiral carbon nanotube of claim 1 , wherein the ultra-long chiral carbon nanotube has a length between 1.5 nm and 3.5 nm; a difference between two helix angles of respective layers is α, wherein α is greater than 0° and less than 15°; the double-walled carbon nanotube has at least one wall with a helix angle β, wherein β is greater than 25° or β is between 16° and 22°.

4. The ultra-long chiral carbon nanotube of claim 3 , wherein β is greater than 25° and equal to or less than 30°, the diameter of the double-walled carbon nanotube is between about 2 nm and 5.5 nm and a length of the double-walled carbon nanotube is between about 154 nm and 650 nm.

5. The ultra-long chiral carbon nanotube of claim 1 , wherein the diameter of the triple-walled carbon nanotube is between about 2.5 nm and 5.5 nm;
said triple-walled carbon nanotube has at least one wall with a helix angle γ, γ is either greater than 25° or equal to 19±3°, wherein helix angels of the layers of the triple-walled carbon nanotube are different from each other.

6. The ultra-long chiral carbon nanotube of claim 5 , wherein γ is greater than 25° and equal to or less than 30°, and a length of the triple-walled carbon nanotube is between 154 nm˜650 nm.

7. A method for preparing an ultra-long chiral carbon nanotube, comprising:
loading a catalyst in the form of solid, liquid, or gas into a reactor;
placing a substrate into the reactor;
raising a temperature in the reactor to a reaction temperature under protection of an inert reducing gas;
introducing a gas mixture of carbon source and carrier gas into the reactor for reaction;
introducing the inert reducing gas into the reactor after the reaction completed, to prevent a carbon tube from being ablated during cooling;
cooling the reactor; and
obtaining the ultra-long chiral carbon nanotube once the reactor drops to room temperature, wherein the ultra-long chiral carbon nanotube has a diameter between about 1.5 nm and 5.5 nm and has a length between about 100 mm and 650 mm.

8. The method of claim 7 , wherein the catalyst comprises at least one of a transition metal element and a transition metal compound, and the transition metal element is selected from a group consisting of Fe, Co, Ni, Cu, Zn, Cr, Ti, Pd, Pt, and Au; wherein the catalyst is loaded into the reactor through at least one of following manners: spin coating, imprinting, steam plating, and vapor deposition.

9. The method of claim 7 , wherein during placing the substrate into the reactor, the reaction temperature is between about 900° C. and 1200° C. and reaction time is between about 6 minutes and 50 minutes.

10. The method of claim 9 , wherein
when the reaction time is between about 6 minutes and 15 minutes, a first ultra-long chiral carbon nanotube is obtained, and the first ultra-long chiral carbon nanotube has a length of L 1 and a purity of 50-60%, wherein L 1 is greater than 50 mm and equal to or less than 100 mm;
when the reaction time is between about 20 minutes and 30 minutes, a second ultra-long chiral carbon nanotube is obtained, and the second ultra-long chiral carbon nanotube has a length of L 2 and a purity of 80-90%, wherein L 2 is greater than about 100 mm and equal to or less than about 150 mm; and
when the reaction time is between about 35 minutes and 50 minutes, a third ultra-long chiral carbon nanotube is obtained, and the third ultra-long chiral carbon nanotube has a length of L 3 and a purity of 100%, wherein L 3 is greater than about 150 mm and equal to or less than about 650 mm.

11. The method of claim 7 , wherein during placing the substrate into the reactor, when the carbon source is reacting in the reactor, the ultra-long chiral carbon nanotube is grown on the substrate at a growth rate of about 70-150 μm/s.

12. The method of claim 7 , wherein during placing the substrate into the reactor, when the carbon source is reacting in the reactor, an external filed is in-situ introduced at any time of the reaction to assist growth of the ultra-long chiral carbon nanotube, wherein the external filed comprises at least one of an electric field, a magnetic field, a sound field, and a light wave.

13. The method of claim 7 , wherein during placing the substrate into the reactor, before the temperature is raised to the reaction temperature, the temperature in the reactor is raised with a rate of about 10° C./min to 60° C./min.

14. The method of claim 7 , wherein the inert reducing gas is a mixture of inert gas and hydrogen.

15. The method of claim 7 , wherein the carrier gas is hydrogen and in the carrier gas, a volume ratio of hydrogen in the carrier gas to carbon source is about 1:1 to 5:1.

16. The method of claim 7 , wherein the carrier gas has a water content of about 0.3 wt %˜0.6 wt %.

17. The method of claim 7 , wherein the carbon source is selected from a group consisting of methane, ethane, propane, methanol, ethanol, ethylene, propylene, and carbon monoxide.

18. The method of claim 7 , wherein the inert gas is selected as at least one from a group consisting of helium, neon, and argon.

Assignees

• Univ Tsinghua

Inventors

• Zhu Zhenxing
• Wei Fei
• Gao Jun
• Sun Silei

Classifications

• C01B32/158 Primary

  Carbon nanotubes · CPC title

• C01B32/162 Primary

  characterised by catalysts · CPC title

• C01B2202/06

  Multi-walled nanotubes · CPC title

• C01B32/164

  involving continuous processes · CPC title

• C01B2202/04

  Nanotubes with a specific amount of walls · CPC title