Carbon quantum dots and a method of making the same

Patent metadata

Field	Value
Publication number	US-9738827-B1
Application number	US-201615141415-A
Country	US
Kind code	B1
Filing date	Apr 28, 2016
Priority date	Apr 28, 2016
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

The present invention is directed to a method of preparing a carbon quantum dot. The carbon quantum dot can be prepared from a carbon precursor, such as a fullerene, and a complex metal hydride. The present invention also discloses a carbon quantum dot made by reacting a carbon precursor with a complex metal hydride and a polymer containing a carbon quantum dot made by reacting a carbon precursor with a complex metal hydride.

First claim

The invention claimed is:

1. A method for preparing carbon quantum dots, the method comprising:
reacting a carbon precursor with a complex metal hydride,
wherein the carbon precursor comprises a fullerene having 20 or more carbon atoms,
wherein the carbon quantum dots have a size of about 1 nm or greater to about 1000 nm or less.

2. The method according to claim 1 , wherein the fullerene has from 20 to 240 carbon atoms.

3. The method according to claim 2 , wherein the fullerene has from 60 to 240 carbon atoms.

4. The method according to claim 1 , wherein the fullerene comprises a C 60 fullerene.

5. The method according to claim 1 , wherein the weight ratio of the carbon precursor to the complex metal hydride is from 1:10 to 10:1.

6. The method according to claim 1 , wherein the complex metal hydride has the following formula
M x M′ y H n

wherein
M is an alkali metal cation or cation complex,
M′ is a metal or metalloid, and
x, y, and n are independently of one another, 1 or greater.

7. The method according to claim 6 , wherein M is an alkali metal cation and M′ is a Group IIIA metal or metalloid.

8. The method according to claim 6 , wherein M is Li or Na and M′ is Al or B.

9. The method according to claim 1 , wherein the complex metal hydride comprises LiAlH 4 , NaAlH 4 , KAlH 4 , NaBH 4 , KBH 4 , NaGaH 4 , LiGaH 4 , Mg(BH 4 ) 2 , Ca(BH 4 ) 2 , LiNH 2 , NH 3 BH 3 , Mg(NH 2 ) 2 .

10. The method according to claim 1 , wherein the complex metal hydride comprises LiBH 4 .

11. The method according to claim 1 , wherein the reaction occurs under nitrogen gas.

12. The method according to claim 1 , wherein the reaction occurs in the presence of an organic solvent.

13. The method according to claim 12 , wherein the organic solvent comprises tetrahydrofuran or benzene.

14. The method according to claim 1 , wherein the reaction occurs at a temperature of from about 25° C. to about 500° C.

15. The method according to claim 1 , further comprising annealing the carbon quantum dots at a temperature of from about 100° C. to about 500° C.

16. The method according to claim 15 , wherein the annealing is done in the presence of H 2 , H 2 O, NH 3 , H 2 S, or SO 2 .

17. The method according to claim 1 , wherein the carbon quantum dots have a hydrogen to carbon ratio of from 1:100 to 3:1.

18. The method according to claim 1 , wherein the carbon quantum dots have at least one heteroatom.

19. The method according to claim 18 , wherein the heteroatom comprises N, O, S, P, Si, Se, As, Ge, Gd, B, Sb, or Te.

20. The method according to claim 1 , wherein the carbon quantum dots are intercalated with a metal or metalloid selected from Group IA, Group IIA, and Group IIIA.

21. The method according to claim 20 , wherein the metal or metalloid comprises, Li, Na, B, Al, Ca, or Mg.

22. A carbon quantum dot made according to the method of claim 1 .

23. A polymer comprising the carbon quantum dot of claim 22 .

Assignees

• Savannah River Nuclear Solutions Llc

Inventors

• Zidan Ragaiy
• Teprovich Joseph A
• Washington Aaron L

Classifications

• C01B31/0206

  Chemistry & Metallurgy · mapped topic

• C09K11/65 Primary

  containing carbon (in organic compounds C09K11/06) · CPC title

• C08K3/38

  Boron-containing compounds · CPC title

• C01P2006/60

  Optical properties, e.g. expressed in CIELAB-values · CPC title

• C01B32/15

  Nano-sized carbon materials · CPC title