Preparation of nanosized cubic lithium lanthanum zirconate fast ion conductor via facile polymer-chelate combustion route
Nanosized cubic lithium lanthanum zirconate is synthesized by forming a solution including an organic compound and compounds of lithium, lanthanum, and zirconium; drying the solution to yield a solid; and heating the solid in the presence of oxygen to pyrolyze the organic compound to yield a product comprising nanosized cubic lithium lanthanum zirconate.
1. A method of synthesizing cubic lithium lanthanum zirconate nanoparticles, the method comprising:
forming a solution comprising an organic compound and compounds of lithium, lanthanum, and zirconium, wherein the organic compound is poly(vinyl alcohol);
heating the solution to yield a solid; and
calcining the solid in the presence of oxygen to pyrolyze the organic compound to yield a product comprising cubic lithium lanthanum zirconate nanoparticles, wherein heating the solution comprises drying the solution above 150° C.
2. The method of claim 1 , wherein calcining the solid comprises forming a carbonaceous foam comprising the poly(vinyl alcohol) or a degradation product thereof.
3. The method of claim 2 , wherein calcining the solid comprises distributing lithium, lanthanum, and zirconium throughout the carbonaceous foam.
4. The method of claim 1 , wherein the solution comprises lithium, lanthanum, and zirconium in a molar ratio of about 10:3:2.
5. The method of claim 1 , wherein the solution comprises lithium, lanthanum, and zirconium in a molar ratio of about 10.5:3:2.
6. The method of claim 1 , wherein the compounds of lithium, lanthanum, and zirconium are nitrate salts.
7. The method of claim 1 , wherein the compounds of lithium, lanthanum, and zirconium include organic moieties.
8. The method of claim 7 , wherein the compounds of lithium, lanthanum, and zirconium include acetylacetonate.
9. The method of claim 1 , wherein the solution is aqueous or non-aqueous.
10. The method of claim 9 , wherein the solution further comprises an organic solvent.
11. The method of claim 10 , wherein the organic solvent comprises propionic acid or dichloromethane.
12. The method of claim 1 , wherein the product comprises at least 90 wt % of the cubic lithium lanthanum zirconate nanoparticles.
13. The method of claim 1 , wherein the product comprises a total amount of lanthanum zirconate, lanthanum oxide, and lithium zirconate of less than 5 wt %.
14. The method of claim 1 , wherein the product comprises less than 5 wt % of tetragonal lithium lanthanum zirconate.
15. The method of claim 1 , wherein the solution further comprises acetic acid.
16. The method of claim 1 , wherein the solution further comprises an additional metal.
17. The method of claim 16 , wherein the additional metal comprises a transition metal.
18. The method of claim 16 , wherein the additional metal comprises aluminum.
19. The method of claim 16 , wherein the additional metal comprises an alkali metal.
20. The method of claim 1 , wherein heating the solution occurs under reduced pressure, under an inert atmosphere, or both.
21. The method of claim 1 , wherein synthesizing the cubic lithium lanthanum zirconate nanoparticles occurs in the absence of gellation.
22. A method of synthesizing cubic lithium lanthanum zirconate nanoparticles, the method comprising:
forming a solution comprising an organic compound and compounds of lithium, lanthanum, and zirconium, wherein the organic compound is poly(vinyl alcohol),
heating the solution to yield a solid, and
calcining the solid in the presence of oxygen to pyrolyze the organic compound to yield a product comprising cubic lithium lanthanum zirconate nanoparticles,
wherein heating the solution comprises heating to a temperature in a range of room temperature to 250° C. for a length of time in a range of 1 to 24 hours.
23. A method of synthesizing cubic lithium lanthanum zirconate nanoparticles, the method comprising:
forming a solution comprising an organic compound and compounds of lithium, lanthanum, and zirconium, wherein the organic compound is poly(vinyl alcohol),
heating the solution to yield a solid, and
calcining the solid in the presence of oxygen to pyrolyze the organic compound to yield a product comprising cubic lithium lanthanum zirconate nanoparticles,
wherein heating the solution comprises ramping a temperature of the solution to 130° C.