Synthesis of lithium lanthanum zirconate from nanocrystalline lanthanum zirconate
Fabricating a layer including lithium lanthanum zirconate (Li 7 La 3 Zr 2 O 12 ) layer includes forming a slurry including lanthanum zirconate (La 2 Zr 2 O 7 ) nanocrystals, a lithium precursor, and a lanthanum precursor in stoichiometric amounts to yield a dispersion including lithium, lanthanum, and zirconium. In some cases, the dispersion includes lithium, lanthanum, and zirconium in a molar ratio of 7:3:2. In certain cases, the slurry includes excess lithium. The slurry is dispensed onto a substrate and dried. The dried slurry is calcined to yield the layer including lithium lanthanum zirconate.
1. A method of fabricating a layer comprising lithium lanthanum zirconate Li 7 La 3 Zr 2 O 12 the method comprising:
forming a slurry comprising lanthanum zirconate La 2 Zr 2 O 7 nanocrystals, a lithium-containing compound, and a lanthanum-containing compound to yield a dispersion comprising lithium, lanthanum, and zirconium;
dispensing the slurry onto a substrate;
drying the slurry to form a dried slurry; and
calcining the dried slurry to yield the layer comprising lithium lanthanum zirconate.
2. The method of claim 1 , wherein the lithium-containing compound comprises lithium nitrate.
3. The method of claim 1 , wherein the lanthanum-containing compound comprises lanthanum nitrate.
4. The method of claim 1 , wherein the slurry further comprises a dopant.
5. The method of claim 4 , wherein the dopant comprises at least one of aluminum, gallium, tantalum, niobium, and molybdenum.
6. The method of claim 1 , wherein the slurry further comprises a dispersant.
7. The method of claim 6 , wherein the dispersant comprises at least one of a surfactant, fish oil, poly(acrylic acid) and salts thereof, poly(methacrylic acid) and salts thereof, and phosphate esters.
8. The method of claim 1 , wherein the slurry further comprises a plasticizer.
9. The method of claim 8 , wherein the plasticizer comprises polyethylene glycol, benzyl butyl phthalate, glycerol, or a combination thereof.
10. The method of claim 1 , wherein the slurry further comprises a binder.
11. The method of claim 10 , wherein the binder comprises polyvinylbutyral.
12. The method of claim 1 , wherein disposing the slurry on the substrate comprises casting the slurry on the substrate.
13. The method of claim 12 , wherein casting the slurry on the substrate comprises tape-casting or spin-casting.
14. The method of claim 1 , wherein disposing the slurry on the substrate comprises dip-coating the substrate in the slurry.
15. The method of claim 1 , wherein calcining the dried slurry comprises heating the dried slurry at a temperature between 700° C. and 1200° C. for a few minutes to several hours.
16. The method of claim 1 , wherein forming the slurry comprises forming the slurry in methanol, ethanol, or a combination thereof.
17. The method of claim 1 , wherein the lanthanum zirconate nanocrystals have an average diameter in a range of 5 nm to 50 nm.
18. The method of claim 1 , wherein the lanthanum zirconate nanocrystals have an average diameter in a range of 10 nm to 30 nm.
19. The method of claim 1 , wherein the layer comprises lithium lanthanum zirconate having a grain size of less than 300 nm.
20. The method of claim 1 , wherein a thickness of the layer is in a range of 1 μm to 500 μm.
21. The method of claim 1 , wherein the lithium lanthanum zirconate is cubic phase lithium lanthanum zirconate.
22. The method of claim 1 , wherein the dispersion comprises lithium, lanthanum, and zirconium in a molar ratio of 7:3:2.
23. The method of claim 1 , wherein the dispersion comprises lanthanum and zirconium in a molar ratio of >7 moles lithium to 3 moles lanthanum to 2 moles zirconium.