Electrochromic device based on layer by layer deposition

1. An electrode comprising:

a substrate having a first and a second surface;

a conductive layer;

a multilayer structure comprising alternating layers of at least one polymer layer and at least one layer comprising a dispersion of electroactive chemical bound nanoparticle;

wherein the conductive layer is disposed on the second surface of the substrate, and the multilayer structure is disposed on the conductive layer.

2. The electrode according to claim 1 , wherein a first polymer layer of the multilayer structure is disposed directly on the conductive layer.

3. The electrode according to claim 1 , wherein a first electroactive chemical bound nanoparticle layer of the multilayer structure is disposed directly on the conductive layer.

4. The electrode according to claim 1 , wherein the nanoparticles comprise nanoparticles having at least two different average sizes.

5. The electrode according to claim 1 , wherein the nanoparticles are titanium dioxide.

6. The electrode according to claim 1 , wherein the electroactive chemical is a ruthenium (II) complex, polyaniline, polypyridyl complex, a viologen, or a derivative thereof.

7. The electrode according to claim 1 , wherein the multilayer structure is from 3 to 12 micrometers thick.

8. The electrode according to claim 1 , wherein the substrate is flexible.

9. The electrode according to claim 1 , wherein the average pore size of the at least one layer comprising a dispersion of electroactive chemical bound nanoparticle layer is greater than 5 nm.

10. The electrode according to claim 1 , wherein the polymer of the at least one polymer layer is polyacetylene, poly(para-phenylene)(PPA), poly(para-phenylene-vinylene) (PPV), polypyrrole, polythiophene, polyaniline, polyfluorene, poly(3-hexyl-thiophene), polynaphthalene, poly(p-phenylene sulfide), poly(3,4-alkylendioxythiophene) (PXDOT), or derivatives thereof.

11. The electrode according to claim 1 , wherein the at least one layer comprising dispersed electroactive chemical bound nanoparticles is formed from a dispersion comprising nanoparticles having an average size from 5 nm to 50 nm; and at least one electroactive chemical, wherein the electroactive chemical binds to the surface of the nanoparticles, the dispersion includes agglomerates of the electroactive chemical bound nanoparticles, and a majority of the agglomerates have an average diameter that is not greater than 1 micrometer.

12. The electrode according to claim 11 , wherein the dispersion comprises 50 wt-% or less of nanoparticles.

13. The electrode according to claim 11 , wherein the majority of the agglomerates have an average diameter that is less than 100 nm.

14. An electrochromic article comprising:

a) an electrode according to claim 1 ; and

b) an electrolyte layer disposed on the electrode.

15. The electrochromic article according to claim 14 further comprising a release layer disposed on the electrolyte layer.

16. The electrochromic article according to claim 14 further comprising a counter electrode disposed on the electrolyte layer.

17. The electrochromic article according to claim 16 , wherein the counter electrode comprises antimony doped zinc oxide nanoparticles.

18. The electrochromic article according to claim 16 further comprising a reflective layer disposed between the counter electrode and the electrode.

19. The electrochromic article according to claim 18 , wherein the reflective layer is a flexible reflective porous membrane.

20. The electrochromic article according to claim 19 , wherein the reflective porous membrane comprises at least one polymer, and at least one reflective particle.

21. The electrochromic article according to claim 19 , wherein the reflective porous membrane is from 20 μm to 100 μm thick.