Electrochromic devices with nanostructure thin film cathodes
A method of manufacturing a thin film is provided. The method includes providing a plurality of crystalline cathodic electrochromic particles comprising an alkali metal oxide material, size-reducing the crystalline cathodic electrochromic particles by grinding to produce crystalline cathodic electrochromic nanostructures, providing a substrate, and coating the crystalline cathodic electrochromic nanostructures onto the substrate to produce a thin film, wherein the thin film is an electrochromic thin film.
1. A method of manufacturing a thin film comprising:
providing a plurality of crystalline alkali metal oxide particles, comprising:
at least one alkali metal selected from the group consisting of lithium, potassium, and sodium;
niobium;
an orthorhombic crystal structure; and
A y Nb 2-x M x O 5±z , where A is the alkali metal, M is a metal other than niobium, x is from 0 to 1, y is from greater than 0 to 0.5, and z is from −0.5 to 0.5;
size-reducing the crystalline alkali metal oxide particles by grinding to produce crystalline alkali metal oxide nanostructures;
providing a substrate; and
coating the crystalline alkali metal oxide nanostructures onto the substrate to produce a thin film, wherein the thin film is an electrochromic thin film.
2. The method of claim 1 , wherein the crystalline alkali metal oxide particles are produced via methods selected from the group consisting of conventional solid state reactions comprising repetitive heating and grinding cycles, hydrothermal synthesis, sol-gel synthesis methods where reactive species are hydrolyzed to form colloids, inert atmosphere reactions, nanosynthesis reactions, precursor decomposition, calcination, melting, and combinations thereof.
3. The method of claim 1 , wherein the crystalline alkali metal oxide particles are produced using a thermal treatment, wherein the temperature range of the thermal treatment is from 700° C. to 1000° C.
4. The method of claim 1 , wherein the crystalline alkali metal oxide particles are produced using a thermal treatment, wherein the temperature range of the thermal treatment is from 100° C. to 400° C.
5. The method of claim 1 , wherein the coating the crystalline alkali metal oxide nanostructures onto the substrate to produce a thin film step comprises:
preparing an ink comprising the crystalline alkali metal oxide nanostructures and at least one solvent, wherein the ink does not comprise a binder material;
coating the ink onto a substrate; and
drying the coated ink at a temperature from 100° C. to 300° C. to produce the thin film.
6. The method of claim 1 , wherein the providing a substrate step comprises providing a plastic substrate with a softening point less than 300° C.
7. The method of claim 1 , wherein the providing a substrate step comprises providing a substrate with a softening point less than 600° C.
8. The method of claim 1 , wherein the thin film is deposited to form an electrochromic cathode layer in an electrochromic device.
9. The method of claim 1 , wherein M is a transition metal, a lanthanide, or an actinide.
10. The method of claim 1 , wherein M is in an octahedral coordination geometry.
11. A method of manufacturing a thin film comprising:
providing a plurality of crystalline alkali metal oxide particles, comprising:
at least one alkali metal selected from the group consisting of lithium, potassium, and sodium;
niobium;
a pyrochlore crystal structure; and
A y Nb 2-x M x O 5±z , where A is the alkali metal, M is a metal other than niobium,
x is from 0 to 1, y is from greater than 0 to 0.5, and z is from −0.5 to 0.5;
size-reducing the crystalline alkali metal oxide particles by grinding to produce crystalline alkali metal oxide nanostructures;
providing a substrate; and
coating the crystalline alkali metal oxide nanostructures onto the substrate to produce a thin film, wherein
the thin film is an electrochromic thin film.
12. The method of claim 11 , wherein the crystalline alkali metal oxide particles are produced via methods selected from the group consisting of conventional solid state reactions comprising repetitive heating and grinding cycles, hydrothermal synthesis, sol-gel synthesis methods where reactive species are hydrolyzed to form colloids, inert atmosphere reactions, nanosynthesis reactions, precursor decomposition, calcination, melting, and combinations thereof.
13. The method of claim 11 , wherein the crystalline alkali metal oxide particles are produced using a thermal treatment, wherein the temperature range of the thermal treatment is from 700° C. to 1000° C.
14. The method of claim 11 , wherein the crystalline alkali metal oxide particles are produced using a thermal treatment, wherein the temperature range of the thermal treatment is from 100° C. to 400° C.
15. The method of claim 11 , wherein the coating the crystalline alkali metal oxide nanostructures onto the substrate to produce a thin film step comprises:
preparing an ink comprising the crystalline alkali metal oxide nanostructures and at least one solvent, wherein the ink does not comprise a binder material;
coating the ink onto a substrate; and
drying the coated ink at a temperature from 100° C. to 300° C. to produce the thin film.
16. The method of claim 11 , wherein the providing a substrate step comprises providing a plastic substrate with a softening point less than 300° C.
17. The method of claim 11 , wherein the providing a substrate step comprises providing a substrate with a softening point less than 600° C.
18. The method of claim 11 , wherein the thin film is deposited to form an electrochromic cathode layer in an electrochromic device.
19. The method of claim 11 , wherein M is a transition metal, a lanthanide, or an actinide.
20. The method of claim 11 , wherein M is in an octahedral coordination geometry.