Fullerene derivatives and their applications in organic photovoltaics

Patent metadata

Field	Value
Publication number	US-9637384-B2
Application number	US-201514799568-A
Country	US
Kind code	B2
Filing date	Jul 14, 2015
Priority date	Aug 8, 2014
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

The present invention relates to new fullerene derivatives of formulae 1a-d, 2 and 3:

method of synthesizing said derivatives, and applications thereof in organic photovoltaics, e.g., organic solar cells. In particular, the fullerene derivatives of the present invention are soluble in non-halogenated solvents such that an environmental-friendly and low-cost fabrication method for industrialization of solar cell based on the new fullerene derivatives is provided. An ink formulation for forming a thin film on a substrate of organic photovoltaics comprising at least one of the fullerene derivatives of the present invention is also provided. Greater than 3% power conversion efficiency of the organic solar cells (area=0.16 cm 2 ) formed based on the fullerene derivatives of the present invention with less pollution and lower cost in fabrication can be achieved in the present invention.

First claim

What is claimed is:

1. A fullerene derivative having formula 1a-d:

wherein R 1 , R 2 and R 3 are independently selected from the group consisting of hydrogen, alkyl group, substituted alkyl group, alkoxy group, aryl group, and substituted alkoxy group; n is 0 or 1;
wherein when n is 0 and any two of R 1 R 2 and R 3 are methyl, one of R 1 R 2 and R 3 is selected from the group consisting of hydrogen, alkyl group having at least 2 carbons, substituted alkyl group, alkoxy group, aryl group, and substituted alkoxy group.

2. The fullerene derivative of claim 1 , wherein the derivative has the following formula 1a:

3. The fullerene derivative of claim 1 , wherein the derivative has the following formula 1b:

4. The fullerene derivative of claim 1 , wherein the derivative has the following formula 1c:

5. The fullerene derivative of claim 1 , wherein the derivative has the following formula 1d:

6. The fullerene derivative of claim 1 , wherein n is 0, the ester group at side chain of said derivative is replaced by aryl group and R 1 R 2 and R 3 are independently selected from the group consisting of hydrogen, alkyl group, aryl group, substituted alkyl group, alkoxy group, and substituted alkoxy group, and the formula of said derivative having said ester group been replaced by aryl group is as follows:

wherein Ar is a simple or substituted aryl group.

7. The fullerene derivative of claim 6 , wherein said simple or substituted aryl group comprises one of the following formulae:

where X is F, Cl, or CN;

where m=1, 2, or 3; n=0 to 6;

where m=1, 2, or 3; n=0 to 6; or

wherein n=0 to 6.

8. The fullerene derivative of claim 6 , wherein said fullerene derivative comprises compounds of any of the following formulae:

9. The fullerene derivative of claim 1 , wherein the ester group and silyl group are replaced by aryl group and amine group, respectively, and the formula of said derivative having the ester group and silyl group replaced by aryl group and amine group, respectively, is as follows:

wherein Ar is a simple or substituted aryl group; R 1 and R 2 are independently selected from the group consisting of hydrogen, alkyl group, substituted alkyl group, alkoxy group, substituted alkoxy group, and cyclic group thereof.

10. The fullerene derivative of claim 9 , wherein said cyclic group for R 1 and R 2 comprises one of the following formulae:

11. A method of synthesizing the fullerene derivative of claim 1 , said method comprising:
a) reacting fullerene (2.8 mmol) with 2,6-dimethyl benzoic acid (28 mmol) in the presence of FeCl 3 (56 mmol) and 1,1,2,2-tetrachloroethane (100 mL) (TCE), and at room temperature (r.t.) for 5 hours to obtain an intermediate product of formula 1:

b) reacting said intermediate product of formula 1 (1.0 mmol) with a corresponding silyl chloride reagent (20 mmol) having the following general formula:

in the presence of 4-(dimethylamino)pyridine (0.2 mmol) and additional pyridine (60 mL) at room temperature (r.t.) for one day to obtain the compound of formulae 1a-d:

wherein R 1 R 2 and R 3 are independently selected from the group consisting of hydrogen, alkyl group, substituted alkyl group, alkoxy group, aryl group, and substituted alkoxy group; n is 0 or 1;
wherein when n is 0 and any two of R 1 R 2 and R 3 are methyl, one of R 1 R 2 and R 3 is selected from the group consisting of hydrogen, alkyl group having at least 2 carbons, substituted alkyl group, alkoxy group, aryl group, and substituted alkoxy group.

12. The method of claim 11 , wherein said silyl chloride reagent comprises chlorodimethylphenylsilane, (chloromethly)dimethylphenlysilane, n-butyldimethylchlorosilane, and t-butylchlorodimethylsilane.

13. The method of claim 11 , wherein the compounds of formulae 1a-d are obtained in no less than 500 mg per batch in about 50% yield.

14. A method of synthesizing the fullerene derivative of claim 6 , said method comprising:
a) reacting fullerene (1.0 mmol) with Ar—NH—NH 2 .HCl (2.0 mmol) and NaNO 2 (3.0 mmol) in toluene (300 mL)-H 2 O (30 mL) to form an intermediate product of formula 2′:

b) reacting said intermediate product of formula 2′ (1.0 mmol) with a silyl chloride reagent (20 mmol) having the following formula:

in the presence of 4-(dimethylamino)pyridine (0.2 mmol) and additional pyridine (60 mL) at room temperature for 1 day to obtain the compound of formula 2:

wherein Ar is a simple or substituted aryl group or substituted thienyl group; R 1 R 2 and R 3 are independently selected from the group consisting of hydrogen, alkyl group, aryl group, substituted alkyl group, alkoxy group, and substituted alkoxy group.

15. The method of claim 14 , wherein said simple or substituted aryl group or substituted thienyl group comprises one of the following formulae:

where X is F, Cl, or CN;

where m=1, 2, or 3; n=0 to 6;

where m=1, 2, or 3; n=0 to 6; or

wherein n=0 to 6.

16. The method of claim 14 , wherein yield of the compound of formula 2 is 23%.

17. A method of synthesizing the fullerene derivative of claim 9 , said method comprising:
a) reacting fullerene with Ar—MgBr t

Assignees

• Nano & Advanced Materials Inst Ltd

Inventors

• Wong Wing Leung
• Leung Lai To
• Zhang Liang
• Chow Chi Mei
• Zhu Haojun
• Lai Lai Fan
• Ho Kwok Keung Paul

Classifications

• C07C2604/00

  Fullerenes, e.g. C60 buckminsterfullerene or C70 · CPC title

• C07D207/323

  with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to the ring nitrogen atoms · CPC title

• C07C67/05

  with oxidation · CPC title

• C07D209/18

  Radicals substituted by carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals · CPC title

• C07F7/081

  comprising at least one atom selected from the elements N, O, halogen, S, Se or Te · CPC title