Electrochromic films prepared by supramolecular self-assembly

• US 20110006272A1
• Filed: 12/17/2009
• Published: 01/13/2011
• Est. Priority Date: 12/18/2008
• Status: Abandoned Application

• Current Assignee: BASF SE
• Original Assignee: BASF SE
• Inventors: Tieke, Bernd, Rabindranath, Aravinda Raman, Maier, Anna
• Application Number:
  US12/640,203
• Publication Number:
  US 20110006272A1
• Time in Patent Office: Days
• US Class Current: 252/583
• CPC Class Codes: C09K 2211/1416 Condensed systems
• CPC Class Codes: C09K 2211/1425 Non-condensed systems
• CPC Class Codes: C09K 2211/1433 bridged by heteroatoms, e.g. N, P, Si or B
• CPC Class Codes: C09K 2211/1466 containing nitrogen as the only heteroatom
• CPC Class Codes: C09K 9/02 Organic tenebrescent materials

Abstract

Highly active and durable electrochromic films are prepared with good thickness control in the nanometer range by alternate application of a metal salt solution and a solution of a π-conjugated polymer having metal complexing side chains, for example, polymers having side chains comprising terpyridine (tpy) groups. Thus a robust, crosslinked organo-metallic network of a known, desired thickness with excellent electroactive properties is readily prepared.

Claims

1. A method for preparing electrochromic films on a substrate which substrate comprises a material selected from the group consisting of a naturally occurring organic polymer, synthetic polymer, metal, mineral, glass and ceramic, which method comprises contacting at least one surface of the substrate with a solution of a metal salt to produce a metal salt treated surface and in a separate step contacting the metal salt treated surface with a solution of a π

-conjugated polymer which polymer comprises a repeating unit of the formula

2. The method according to claim 1 wherein

in R—

Ar—

R, Ar is an unsubstituted or substituted phenyl, biphenyl, naphthyl, fluorene, diphenylamine, pyrrole or thiophene group and each R is independently a direct bond, nitrogen atom, ethylene or acetylene;

G is a nitrogen atom, a phenylene or a substituted phenylene;

L is unsubstituted or substituted phenylene, biphenylene, naphthalene, ethenylene, ethynylene, pyrrole or thiophene; and

Cg is terpyridine, benzimidazole, or terpyridine or benzimidazole substituted one or more times by one or more groups selected from C_1-8 alkyl C_1-8 alkoxy, and C_1-8 alkylcarbonyl.

3. The method according to claim 1 wherein the metal of the metal salt is Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ru, Os, Ag, Au, Zr, Mo, W, Rh, Pd or Pt.

4. The method according to claim 1 wherein the substrate upon which the film is prepared comprises a thermoplastic polymer, quartz, glass or metal.

5. The method according to claim 4 wherein the substrate upon which the film is prepared is quartz, glass or glass upon which is layered a metal containing material such as indium tin oxide.

6. The method according to claim 1 wherein the surface of the substrate upon which the film is prepared is first pretreated with polyelectrolytes to form ions on the surface.

7. The method according to claim 6 wherein one or more polyelectrolyte layers of polystyrene sulfonate and/or polyethyleneimine are applied to the surface of the substrate to prepare a negatively charged surface.

8. The method according to claim 3 wherein the metal salt is a hexafluorophosphate or a 2,2′

-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid salt.

9. The method according to claim 8 wherein the metal salt is a Zn(II), Ni(II) or Co(II) salt.

10. The method according to claim 1 comprising a sequence of steps i) through iv) wherein the substrate is

i) immersed into the solution of a metal salt for a selected period of time, removed, then

ii) immersed into a rinsing solvent for a selected period of time, removed, then

iii) immersed into the solution of the a π

-conjugated polymer for a selected period of time, removed, then

iv) optionally immersed into a rinsing solvent for a selected period of time,

wherein each step i through iv is performed once or more than once, the selected period of time for each step is independently from about 1 second to about 60 minutes, and the sequence of steps is performed once or more than once.

11. The method according to claim 10 wherein the selected period of time for each step is independently from about 1 minute to about 30 minutes.

12. The method according to claim 10 wherein the substrate upon which the film is prepared comprises a thermoplastic polymer, quartz, glass or metal and the metal of the metal salt is Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ru, Os, Ag, Au, Zr, Mo, W, Rh, Pd or Pt.

13. The method according to claim 12 wherein the substrate upon which the film is prepared is quartz, glass or glass upon which is layered a metal containing material such as indium tin oxide.

14. The method according to claim 10 wherein the surface of the substrate upon which the film is prepared is first pretreated with polyelectrolytes to form ions on the surface.

15. The method according to claim 14 wherein one or more polyelectrolyte layers of polystyrene sulfonate and/or polyethyleneimine are applied to the surface of the substrate to prepare a negatively charged surface.

16. The method according to claim 10 wherein the metal salt is a hexafluorophosphate or a 2,2′

-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid salt.

17. The method according to claim 16 wherein the metal salt is a Zn(II), Ni(II) or Co(II) salt.

19. The electrochromic film obtained according to the method of claim 1.

20. The coated substrate obtained according to the method of claim 1.

18. A method for preparing electrochromic films on a substrate wherein a coordination polymer containing alternating layers of metal ions and organic ligands, which method comprises the step wherein the metal ions of an already prepared coordination polymer are exchanged with alternate metal ions by exposure of the coordination polymer to a solution of a salt of the alternate metal ion.