Lithium lanthanum zirconate thin films
Forming a lithium lanthanum zirconate thin film includes disposing zirconium oxide on a substrate to yield a zirconium oxide coating, contacting the zirconium oxide coating with a solution including a lithium salt and a lanthanum salt, heating the substrate to yield a dried salt coating on the zirconium oxide coating, melting the dried salt coating to yield a molten salt mixture, reacting the molten salt mixture with the zirconium oxide coating to yield lithium lanthanum zirconate, and cooling the lithium lanthanum zirconate to yield a lithium lanthanum zirconate coating on the substrate. In some cases, the zirconium oxide coating is contacted with an aqueous molten salt mixture including a lithium salt and a lanthanum salt, the molten salt mixture is reacted with the zirconium oxide coating to yield lithium lanthanum zirconate, and the lithium lanthanum zirconate is cooled to yield a lithium lanthanum zirconate coating on the substrate.
1. A method of coating a substrate, the method comprising:
disposing zirconium oxide on a substrate to yield a zirconium oxide coating on the substrate;
contacting the zirconium oxide coating with a solution comprising a lithium salt and a lanthanum salt;
heating the substrate to yield a dried salt coating on the zirconium oxide coating;
melting the dried salt coating to yield a molten salt mixture;
reacting the molten salt mixture with the zirconium oxide coating to yield lithium lanthanum zirconate; and
cooling the lithium lanthanum zirconate to yield a lithium lanthanum zirconate coating on the substrate.
2. The method of claim 1 , wherein disposing zirconium oxide on the substrate comprises atomic layer deposition or plasma-enhanced atomic layer deposition of zirconium oxide on the substrate.
3. The method of claim 2 , wherein disposing the zirconium oxide on the substrate further comprises disposing additional zirconium oxide on the zirconium oxide coating with a chemical vapor deposition or sol-gel process.
4. The method of claim 2 , wherein the zirconium oxide used to form the zirconium oxide coating is in the form of zirconium oxide nanoparticles.
5. The method of claim 1 , wherein the zirconium oxide coating is amorphous.
6. The method of claim 1 , wherein the solution is homogeneous.
7. The method of claim 1 , wherein the lithium salt comprises lithium nitrate.
8. The method of claim 1 , wherein the lanthanum salt comprises lanthanum nitrate.
9. The method of claim 1 , wherein the solution further comprises a zirconium salt.
10. The method of claim 9 , wherein the zirconium salt comprises a nitrate salt.
11. The method of claim 1 , wherein contacting the solution with the zirconium oxide coating comprises spraying the solution on the zirconium oxide coating.
12. The method of claim 1 , wherein contacting the solution with the zirconium oxide coating comprises drop casting the solution on the zirconium oxide coating.
13. The method of claim 1 , wherein heating the substrate comprises removing liquid from the solution.
14. The method of claim 1 , wherein melting the dried salt coating comprises heating the substrate to at least 400° C.
15. The method of claim 1 , wherein contacting the solution with the zirconium oxide coating comprises wetting the zirconium oxide coating with the solution.
16. The method of claim 1 , wherein the substrate is planar.
17. The method of claim 1 , wherein the substrate comprises protrusions and recessions.
18. The method of claim 1 , wherein the lithium lanthanum zirconate coating is polycrystalline or nanocrystalline.
19. The method of claim 1 , wherein a thickness of the lithium lanthanum zirconate coating is in a range of 1 micron to 10 microns.
20. The method of claim 1 , wherein the solution comprises a polar solvent.
21. The method of claim 20 , wherein the polar solvent comprises water.
22. The method of claim 20 , wherein the polar solvent comprises an organic solvent.
23. The method of claim 22 , wherein the organic solvent comprises methanol.