Green electrochromic (EC) material and device

• US 7,298,541 B2
• Filed: 09/09/2005
• Issued: 11/20/2007
• Est. Priority Date: 06/25/2002
• Status: Expired due to Term

• Current Assignee: University of Washington
• Original Assignee: University of Washington
• Inventors: Taya, Minoru, Xu, Chunye, Liu, Lu
• Primary Examiner(s): Mack; Ricky
• Assistant Examiner(s): Dinh; Jack
• Application Number:
  US11/223,794
• Publication Number:
  US 20070177243A1
• Time in Patent Office: 802 Days
• Field of Search: 359265-275
• US Class Current: 359/265
• CPC Class Codes: C08G 61/122 derived from five- or six-membered heterocyclic compounds, other than imides
• CPC Class Codes: C08G 61/126 with a five-membered ring containing one sulfur atom in the ring
• CPC Class Codes: C09K 2211/1007 Non-condensed systems
• CPC Class Codes: C09K 2211/1011 Condensed systems
• CPC Class Codes: C09K 2211/1044 containing two nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/1092 containing sulfur as the only heteroatom
• CPC Class Codes: C09K 9/02 Organic tenebrescent materials

Abstract

Three green EC materials based on thiophene, and a green EC material based on pyrazine are disclosed. A first thiophene derivative (2,3-Di-thiophen-2-yl-thieno[3,4-b]pyrazine), which was previously investigated as a nonlinear optical material, is here disclosed for its use as an EC material, and for its incorporation into an EC device. Synthesis of two new thiophene derivatives (2,5-di(thien-2-yl)-3,4-di(2,2,2-trifluoro-ethoxy)-thiophene and 2,5-(2,3-dihydro-thieno[3,4-b][1,4]dioxin-5-yl)-3,4-di(2,2,2-trifluoro-ethoxy)-thiophene), and a new pyrazine derivative (2,3-dibenzyl-5,7-di(thien-2-yl)thieno[3,4-b]pyrazine) are also disclosed, since these materials are all able to selectively change to a green color state, and can be polymerized to achieve a green EC polymer.

Claims

1. An electrochromic device switchable between a first substantially transparent state and a second state in which the electrochromic device exhibits a saturated green color, comprising:

(a) a transparent electrode;

(b) an electrochromic organic material which in a first state is generally transparent and in a second state exhibits a saturated green color, wherein the electrochromic organic material is based on 2,3-dibenzyl-5,7-di(thien-2-yl)thieno[3,4-b]pyrazine; and

(c) an electrolyte.

2. The electrochromic device of claim 1, wherein the electrochromic organic material based on 2,3-dibenzyl-5,7-di(thien-2-yl)thieno[3,4-b]pyrazine comprises a halogenated derivative of 2,3-dibenzyl-5,7-di(thien-2-yl)thieno[3,4-b]pyrazine.

3. An electrochromic device comprising:

(a) a transparent electrode;

(b) an electrochromic organic material which in a first state is generally transparent and in a second state exhibits a saturated green color, wherein the electrochromic organic material comprises 2,3-Di-thiophen-2-yl-thieno[3,4-b]pyrazine; and

(c) an electrolyte.

4. The electrochromic device of claim 3, wherein the electrolyte comprises a liquid, and the electrochromic organic material is dissolved in the liquid.

5. The electrochromic device of claim 3, further comprising a reference electrode.

6. The electrochromic device of claim 3, further comprising a charge balancing molecule.

7. The electrochromic device of claim 6, wherein the charge balancing molecule comprises 5,10-dihydro-5,10,dimethylphenazine.

8. An electrochromic device comprising:

(a) a transparent electrode;

(b) an electrochromic organic material which in a first state is not green and in a second state exhibits a green color, the electrochromic organic material exhibiting a single absorbance band, the electrochromic organic material being based on 2,5-di(thien-2-yl)-3,4-di(2,2,2-trifluoro-ethoxy)-thiophene; and

(c) an electrolyte.

9. An electrochromic device comprising:

(a) a transparent electrode;

(b) an electrochromic organic material which in a first state is not green and in a second state exhibits a green color, the electrochromic organic material exhibiting a single absorbance band, the electrochromic organic material being based on 2,5-(2,3-dihydro-thieno[3,4-b][1,4]dioxin-5-yl)-3,4-di(2,2,2-trifluoro-ethoxy)-thiophene; and

(c) an electrolyte.