Transparency and color tunable electro-optical device using colloidal core/shell nanoparticles

1. A product, comprising:

a mixture comprising a solvent and generally spherical colloidal nanoparticles, the colloidal nanoparticles each having a core and a shell surrounding the core; and

an electrode,

wherein the mixture is characterized as having a transparency to light in a predetermined wavelength range, wherein the transparency increases as a voltage of the electrode increases.

2. The product of claim 1 , wherein the colloidal nanoparticles migrate toward one side of the mixture upon application of the voltage to the electrode.

3. The product of claim 1 , wherein at least one electrode is transparent.

4. The product of claim 1 , wherein at least some of the cores are light emitting.

5. The product of claim 1 , wherein at least some of the cores include a colorant applied to a base material of the cores.

6. The product of claim 1 , wherein a color hue of the mixture changes as the transparency changes.

7. The product of claim 1 , wherein the mixture is characterized as having a transparency of at least 90% light transmission upon application of a predetermined voltage to the electrode.

8. The product of claim 1 , wherein the predetermined wavelength range is only a portion of the wavelengths in the ultraviolet to infrared range, wherein the transparency of the mixture does not significantly change for a second wavelength range in the ultraviolet to infrared range as the voltage of the electrode increases.

9. The product of claim 1 , wherein the shell is silicon-based.

10. The product of claim 1 , wherein the shell has a positive charge.

11. The product of claim 1 , wherein the shell has a negative charge.

12. The product of claim 1 , wherein the solvent is a polar solvent, wherein a boiling point of the solvent is greater than about 150 degrees Celsius.

13. The product of claim 1 , further comprising at least one spacer forming a chamber having sides defining an interior, wherein the mixture is in the interior of the chamber.

14. The product of claim 1 , the mixture having a specific color, the mixture being characterized as changing color across the visible spectrum in direct correlation to a concentration of the nanoparticles wherein a concentration of the nanoparticles is selected to provide the specific color of the mixture.

15. The product of claim 14 , wherein changing the concentration of the nanoparticles changes the color of the mixture across a visible spectrum.

16. A product, comprising:

a plurality of generally spherical colloidal nanoparticles each having a core and a shell surrounding the core,

wherein at least some of the cores include a colorant applied to a base material of the cores.

17. The product of claim 16 , wherein the nanoparticles have an average diameter in a range of about 50 to about 200 nanometers.

18. The product of claim 16 , wherein at least some of the cores are light emitting.

19. The product of claim 16 , wherein the core is light absorbing in selected regions of the electromagnetic spectrum.

20. The product of claim 16 , wherein the core is light reflecting in selected regions of the electromagnetic spectrum.

21. The product of claim 16 , wherein the core is silicon-based.

22. The product of claim 16 , wherein the shell has a positive charge.

23. The product of claim 16 , wherein the shell has a negative charge.

24. The product of claim 1 , wherein a concentration of the generally spherical colloidal nanoparticles in the mixture is in a range of about 5 to about 30 weight % in the mixture.

25. The product of claim 2 , wherein the mixture is physically characterized as having a greater relative transparency when the colloidal nanoparticles are migrated toward the one side of the mixture upon application of the voltage to the electrode.

26. The product of claim 1 , wherein the mixture is characterized as having a random particle structure in an absence of an applied voltage.