Electrochromic materials, devices and process of making

• US 6,647,166 B2
• Filed: 07/09/2001
• Issued: 11/11/2003
• Est. Priority Date: 08/17/2000
• Status: Expired due to Term

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Richardson, Thomas J.
• Primary Examiner(s): Ullah, Akm E.
• Assistant Examiner(s): CONNELLY, MICHELLE R
• Application Number:
  US09/901,969
• Publication Number:
  US 20020044717A1
• Time in Patent Office: 855 Days
• Field of Search: 385/16-23, 385/24, 359/124, 359/127, 359/128
• US Class Current: 385/16
• CPC Class Codes: G02F 1/1524 Transition metal compounds
• CPC Class Codes: G02F 1/19 based on variable-reflection or variable-refraction elements not provided for in groups G02F1/015 - G02F1/169
• CPC Class Codes: G02F 2202/34 Metal hydrides materials

Abstract

Thin films of transition metal compositions formed with magnesium that are metals, alloys, hydrides or mixtures of alloys, metals and/or hydrides exhibit reversible color changes on application of electric current or hydrogen. Thin films of these materials are suitable for optical switching elements, thin film displays, sun roofs, rear-view mirrors and architectural glass.

Claims

1. A switching device comprising a substrate and a mono-layer film capable of undergoing a reversible change in light transmittance or reflectance, said film comprising a transition metal composition which includes magnesium, said transition metal composition consisting essentially of at least one transition metal chosen from the group consisting of Ti, V, Cr, Mn, Fe, Go, Ni, Cu, Zn, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, Os, Ir, Pt, Au and Hg, wherein switching occurs by the formation or decomposition of a hydride.

2. A switching device as claimed in claim 1, wherein the transition metal composition is a metal, an alloy, a hydride or mixture of metals, alloys and/or hydrides.

3. A switching device as claimed in claim 2, wherein the transition metal composition is an alloy of Mg and a transition metal chosen from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn.

4. A switching device as claimed in claim 3, wherein the alloy is Mg₂Ni, Mg₂Fe or Mg₂Co.

5. A switching device as claimed in claim 1, wherein the transition metal composition is a ternary combination of two transition metals and magnesium.

6. A switching device as claimed in claim 5, wherein the ternary combination comprises magnesium and two metals chosen from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn.

7. A switching device as claimed in claim 6, wherein the film is Ni_xCo_1-xMg_y, where 0<

x<

1, and 2<

y<

12.

8. A switching device as claimed in claim 5, wherein the ternary combination comprises a combination of magnesium and a transition metal alloy chosen from the group consisting of Fe_xTi_1-x (0<

x<

1), V_xTi_1-x (0<

x<

1), NiTi₂, NiZr₂, Nb and Ta alloys.

9. A display device incorporating at least one switching device as claimed in claim 1.

10. An optical recording device incorporating at least one switching device as claimed in claim 1.

11. A switching device as claimed in claim 1, characterized in that the film can be reversible switched from a reflective, metallic state to a transparent state.

12. A switching device comprising a substrate and a mono-layer film, said film capable of undergoing a reversible change in light transmittance or reflectance, wherein said film comprises elemental mixtures, alloys, hydrides or solutions of the following systems:

Mn—

Mg, Ti—

Mg, Cu—

Mg, Ni(7 wt % V)-Mg and Fe—

Mg, or hydrides of pure Ti or pure V, wherein switching occurs by the formation or decomposition of a hydride.

13. A display device incorporating at least one switching device as claimed in claim 12.

14. An optical recording device incorporating at least one switching device as claimed in claim 12.