Flexible boron nitride nanoribbon aerogel and preparation method thereof

Patent metadata

Field	Value
Publication number	US-12043544-B2
Application number	US-202017277733-A
Country	US
Kind code	B2
Filing date	Jan 2, 2020
Priority date	Feb 22, 2019
Publication date	Jul 23, 2024
Grant date	Jul 23, 2024

Abstract

A flexible boron nitride nanoribbon aerogel has an interconnected three-dimensional porous network structure which is formed by mutually twining and contacting boron nitride nanoribbons and consists of macropores having a pore diameter of more than 50 nm, mesopores having a pore diameter of 2-50 nm and micropores having a pore diameter of less than 2 nm. The preparation method of the flexible boron nitride nanoribbon aerogel includes the following steps: performing high-temperature dissolution on boric acid and a nitrogen-containing precursor to form a transparent precursor solution, preparing the transparent precursor solution into precursor hydrogel, subsequently drying and performing high-temperature pyrolysis to obtain the flexible boron nitride nanoribbon aerogel. The boron nitride nanoribbon aerogel has excellent flexibility and resilience and can withstand different forms of loads from the outside within a wide temperature range.

First claim

What is claimed is:

1. A flexible boron nitride nanoribbon aerogel, comprising an interconnected three-dimensional porous network structure, wherein the interconnected three-dimensional porous network structure is formed by mutually twining and contacting boron nitride nanoribbons and consists of macropores having a pore diameter of more than 50 nm, mesopores having a pore diameter of 2-50 nm and micropores having a pore diameter of less than 2 nm and wherein the boron nitride nanoribbons have a thickness of 1 nm-100 nm and a width of 200 nm-10 μm.

2. The flexible boron nitride nanoribbon aerogel according to claim 1 , wherein the macropores are formed by interconnecting the boron nitride nanoribbons, and each of the boron nitride nanoribbons has the mesopores and the micropores; and/or each of the boron nitride nanoribbons is in a straight, twisted or bent state in the interconnected three-dimensional porous network structure.

3. The flexible boron nitride nanoribbon aerogel according to claim 1 , wherein each of the boron nitride nanoribbons is mainly composed of boron and nitrogen; each of the boron nitride nanoribbons comprises the boron, the nitrogen, carbon and oxygen.

4. The flexible boron nitride nanoribbon aerogel according to claim 1 , wherein the flexible boron nitride nanoribbon aerogel has a density of 1-600 mg/ml; and/or a contact angle between a surface of the flexible boron nitride nanoribbon aerogel and water is 60-170°; and/or the flexible boron nitride nanoribbon aerogel has a thermal conductivity of 0.025-0.5 W/mK; and/or the flexible boron nitride nanoribbon aerogel has a specific surface area of 10-1800 m 2 /g, a pore volume of 0.1-2.0 cm 3 /g, and a porosity of 1-99%.

5. The flexible boron nitride nanoribbon aerogel according to claim 1 , wherein the flexible boron nitride nanoribbon aerogel withstands a selected form of load without breaking and is restored to an original shape when the selected form of load is removed; wherein the selected form of load is selected from the group consisting of external compression, bending, twisting and shearing; wherein the flexible boron nitride nanoribbon aerogel has a flexibility and resilience at a temperature within a temperature range of −196-1000° C.

6. A preparation method of the flexible boron nitride nanoribbon aerogel of claim 1 , comprising:
1) dissolving boric acid and a nitrogen-containing precursor into a solvent to obtain a transparent precursor solution;
2) cooling the transparent precursor solution to obtain a precursor hydrogel;
3) drying the precursor hydrogel to obtain a precursor aerogel; and
4) performing a high-temperature hydrolysis on the precursor aerogel in a protective atmosphere to obtain the flexible boron nitride nanoribbon aerogel.

7. The preparation method according to claim 6 , wherein the nitrogen-containing precursor in step 1) comprises at least one selected from the group consisting of urea, melamine, cyanuric acid, biuret and dimethylguanidine; and/or a molar ratio of the boric acid to the nitrogen-containing precursor is (1:50) -(50:1); and/or the solvent comprises at least one selected from the group consisting of water, methanol, ethanol, ethylene glycol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, acetone and dimethyl sulfoxide; and/or a dissolution temperature is 30-100° C.

8. The preparation method according to claim 6 , wherein in step 2), a cooling temperature is −196-65° C., and a cooling time is 5 min-12 h, and the cooling is performed in an ultrasonic environment or an ultrasonic-free environment; wherein an ultrasonic power is 0.01 W-10000 W, and an ultrasonic time is 0.5 min-12 h; and/or
the drying in step 3) comprises at least one selected from the group consisting of freeze drying, ambient drying, vacuum drying and supercritical drying.

9. The preparation method according to claim 6 , wherein in step 4), a high-temperature hydrolysis temperature is 400-1800° C., and a high-temperature hydrolysis time is 0.5-24 h; and/or the protective atmosphere comprises at least one selected from the group consisting of an nitrogen atmosphere, an inert gas atmosphere, an ammonia atmosphere, a hydrogen atmosphere and an air atmosphere.

10. The flexible boron nitride nanoribbon aerogel according to claim 2 , wherein the flexible boron nitride nanoribbon aerogel withstands a selected form of load without breaking and is restored to an original shape when the selected form of load is removed; wherein the selected form of load is selected from the group consisting of external compression, bending, twisting and shearing; wherein the flexible boron nitride nanoribbon aerogel has a flexibility and resilience at a temperature within a temperature range of −196-1000° C.

11. The flexible boron nitride nanoribbon aerogel according to claim 3 , wherein the flexible boron nitride nanoribbon aerogel withstands a selected form of load without breaking and is restored to an original shape when the selected form of load is removed; wherein the selected form of load is selected from the group consisting of external compression, bending, twisting and shearing; wherein the flexible boron nitride nanoribbon aerogel has a flexibility and resilience at a temperature within a temperature range of −196-1000° C.

12. The flexible boron nitride nanoribbon aerogel according to claim 4 , wherein the flexible boron nitride nanoribbon aerogel withstands a selected form of load without breaking and is restored to an original shape when the selected form of load is removed; wherein the selected form of load is selected from the group consisting of external compression, bending, twisting and shearing; wherein the flexible boron nitride nanoribbon aerogel has a flexibility and resilience at a temperature within a temperature range of −196-1000° C.

13. The flexible boron nitride nanoribbon aerogel according to claim 1 , wherein the boron nitride nanoribbons are in a twisted state in the three-dimensional porous network structure.

14. The flexible boron nitride nanoribbon aerogel according to claim 1 , wherein the boron nitride nanoribbons are in a twisted state in the three-dimensional porous network structure, the flexible boron nitride nanoribbon aerogel has a density of 5-100 mg/mL; a contact angle between a surface of the flexible boron nitride nanoribbon aerogel and water is 120-150°; the flexible boron nitride nanoribbon aerogel has a thermal conductivity of 0.03-0.05 W/mK; the flexible boron nitride nanoribbon aerogel has a specific surface area of 500-1500 m 2 /g, a pore volume of 0.5-1.5 cm 3 /g, and a porosity of 75-97%.

Assignees

• Suzhou Inst Nano Tech & Nano Bionics Sinano Cas

Inventors

• Zhang Xuetong
• Li Guangyong

Classifications

• C01P2006/90

  Other properties not specified above · CPC title

• C01P2006/32

  Thermal properties · CPC title

• C01P2006/17

  Pore diameter distribution · CPC title

• C01P2006/14

  Pore volume · CPC title

• C01P2006/12

  Surface area · CPC title