HIGHLY-FLUORESCENT AND PHOTO-STABLE CHROMOPHORES FOR WAVELENGTH CONVERSION

• US 20150340519A1
• Filed: 01/03/2014
• Published: 11/26/2015
• Est. Priority Date: 01/04/2013
• Status: Active Grant

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Michiharu Yamamoto, Nitto Denko Corporation
• Inventors: YAMAMOTO, MICHIHARU, RACHWAL, MILA
• Granted Patent: US 9,960,294 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: C09K 2211/1011 Condensed systems
• CPC Class Codes: C09K 2211/1014 bridged by heteroatoms, e.g. N, P, Si or B
• CPC Class Codes: C09K 2211/1022 bridged by heteroatoms, e.g. N, P, Si or B
• CPC Class Codes: C09K 2211/1029 containing one nitrogen atom as the heteroatom
• CPC Class Codes: C09K 2211/1044 containing two nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/1051 with sulfur
• CPC Class Codes: C09K 2211/1059 containing three nitrogen atoms as heteroatoms
• CPC Class Codes: H01L 31/02322 comprising luminescent members, e.g. fluorescent sheets upon the device
• CPC Class Codes: H01L 31/055 where light is absorbed and re-emitted at a different wavelength by the optical element directly associated or integrated with the PV cell, e.g. by using luminescent material, fluorescent concentrators or up-conversion arrangements
• CPC Class Codes: H10K 85/657 Polycyclic condensed heteroaromatic hydrocarbons
• CPC Class Codes: Y02E 10/52 PV systems with concentrators
• CPC Class Codes: Y02E 10/549 Organic PV cells

Abstract

The invention provides highly fluorescent materials comprising a single (i=0) or a series (i=1, 2, etc.) of heterocyclic systems. The chromophores are particularly useful for absorption and emission of photons in the visible and near infrared wavelength range. The photo-stable highly luminescent chromophores are useful in various applications, including in wavelength conversion films. Wavelength conversion films have the potential to significantly enhance the solar harvesting efficiency of photovoltaic or solar cell devices.

Claims

1. A chromophore represented by formula I:

2. The chromophore of claim 1, wherein D₁ and D₂ are each independently selected from the group consisting of alkoxyaryl, -aryl-NR′

R″

, and -aryl-aryl-NR′

R″

;

wherein R′ and

R″

are independently selected from the group consisting of alkyl and aryl optionally substituted by alkyl, alkoxy, or —

C(═

O)R;

wherein R is optionally substituted aryl or optionally substituted alkyl;

or one or both of R′ and

R″

forms a fused heterocyclic ring with aryl to which the N is attached to.

3. The chromophore of claim 1, wherein L is independently selected from the group consisting of haloalkyl, alkylaryl, alkyl substituted heteroaryl, arylalkyl, heteroamino, heterocyclic amino, cycloamido, cycloimido, aryloxy, acyloxy, alkylacyl, arylacyl, alkylcarboxy, arylcarboxy, optionally substituted phenyl, and optionally substituted naphthyl.

4. The chromophore of claim 1, provided that when Het is:

5. The chromophore of claim 1, wherein Het is:

6. The chromophore of claim 1, wherein Het is:

7. The chromophore of claim 1, wherein Het is:

8. The chromophore of claim 1, wherein Het is:

20. The chromophore of claim 1, wherein:

X is selected from the group consisting of —

N(A₀)-, —

S—

, and —

Se—

.

21. The chromophore of claim 1, wherein:

Z is selected from the group consisting of —

N(R_a)—

, —

S—

, and —

Se—

.

22. The chromophore of claim 1, wherein:

A₀ is selected from the group consisting of hydrogen, optionally substituted C_1-10 alkyl, optionally substituted aryl, optionally substituted heteroaryl, and optionally substituted alkoxyalkyl.

23. The chromophore of claim 1, wherein:

A₀ is selected from the group consisting of;

hydrogen, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl,

24. The chromophore of claim 1, wherein R_a, R_b, and R_c, are independently selected from the group consisting of hydrogen, optionally substituted C_1-10 alkyl, optionally substituted aryl, optionally substituted heteroaryl, and optionally substituted alkoxyalkyl;

or R_a and R_b, or R_b and R_c, or R_a and R_c, together form an optionally substituted polycyclic ring system.

25. The chromophore of claim 1, wherein R_a, R_b, and R_c, are independently selected from the group consisting of:

hydrogen, methyl, ethyl, propyl, isopropyl butyl isobutyl, tert-butyl, pentyl hexyl,

26. The chromophore of claim 1, wherein R_a and R_b, or R_b and R_c, or R_a and R_c, together form a ring structure selected from the group consisting of:

27. The chromophore of claim 1, wherein:

D₁ and D₂ are each independently selected from group consisting of the following structures;

28. A wavelength conversion luminescent medium comprising an optically transparent polymer matrix and at least one luminescent dye comprising a chromophore of claim 1.

29. The wavelength conversion luminescent medium of claim 28, wherein the polymer matrix comprises a substance selected from the group consisting of polyethylene terephthalate, polymethyl methacrylate, polyvinyl butyral, ethylene vinyl acetate, ethylene tetrafluoroethylene, polyimide, amorphous polycarbonate, polystyrene, siloxane sol-gel, polyurethane, polyacrylate, and combinations thereof.

30. The wavelength conversion luminescent medium of claim 28, wherein the refractive index of the polymer matrix material is in the range of about 1.4 to about 1.7.

31. The wavelength conversion luminescent medium of claim 28, wherein the luminescent dye is present in the polymer matrix in an amount in the range of about 0.01 wt % to about 3 wt %.

32. A photovoltaic module comprising at least one photovoltaic device or solar cell, and a wavelength conversion luminescent medium according to claim 28, wherein the wavelength conversion luminescent medium is positioned such that the incident light passes through the wavelength conversion luminescent medium prior to reaching the photovoltaic device or solar cell.

33. The photovoltaic module of claim 32, wherein the wavelength conversion luminescent medium is a film having a thickness in the range of about 0.1 μ

m to about 1 mm.

34. The photovoltaic module of claim 32, wherein the photovoltaic device or solar cell comprises at least one device selected from the group consisting of a Cadmium Sulfide/Cadmium Telluride solar cell, a Copper Indium Gallium Diselenide solar cell, an amorphous Silicon solar cell, a microcrystalline Silicon solar cell, or a crystalline Silicon solar cell.

35. The photovoltaic module of claim 32, further comprising a refractive index matching liquid or optical adhesive that is used to attach the wavelength conversion luminescent medium to a light incident surface of the photovoltaic device or solar cell.

36. A method for improving the performance of a photovoltaic device of solar cell, comprising applying a wavelength conversion luminescent medium according to claim 28 directly onto the light incident side of the photovoltaic device or solar cell, or encapsulate the wavelength conversion luminescent medium in the photovoltaic device or solar cell.

9. A chromophore represented by formula IIa or formula IIb:

Het₂-A₀-Het₂ 

 

(IIa),

10. The chromophore of claim 9, wherein D₁ and D₂ are each independently selected from the group consisting of alkoxyaryl, -aryl-NR′

R″

, and -aryl-aryl-NR′

R″

;

wherein R′ and

R″

are independently selected from the group consisting of alkyl and aryl optionally substituted by alkyl, alkoxy, or —

C(═

O)R;

wherein R is optionally substituted aryl or optionally substituted alkyl;

or one or both of R′ and

R″

forms a fused heterocyclic ring with aryl to which the N is attached to.

11. The chromophore of claim 9, wherein Het₂ is:

12. The chromophore of claim 9, wherein Het₂ is:

13. The chromophore of claim 9, wherein Het₂ is:

14. The chromophore of claim 9, wherein Het₂ is:

15. A chromophore represented by formula IIIa or formula IIIb:

Het₃-R_a-Het₃ 

 

(IIIa),

16. The chromophore of claim 15, wherein D₁ and D₂ are each independently selected from the group consisting of alkoxyaryl, -aryl-NR′

R″

, and -aryl-aryl-NR′

R″

;

wherein R′ and

R″

are independently selected from the group consisting of alkyl and aryl optionally substituted by alkyl, alkoxy, or —

C(═

O)R;

wherein R is optionally substituted aryl or optionally substituted alkyl;

or one or both of R′ and

R″

forms a fused heterocyclic ring with aryl to which the N is attached to.

17. The chromophore of claim 15, wherein Het₃ is:

18. The chromophore of claim 15, wherein Het₃ is:

19. The chromophore of claim 15, wherein Het₃ is: