Method for making uniform porous surface layer on garnet thin film

Abstract

A solid garnet composition includes a bulk composition having a lithium garnet; and a surface composition having a protonated garnet on at least a portion of the exterior surface of the lithium garnet, such that the protonated garnet is uniformly disposed over the at least a portion of the exterior surface of the lithium garnet. A method of making a solid garnet composition includes pre-treating an air sensitive lithium-containing garnet with water to form a uniform protonated garnet surface composition; and contacting the uniform protonated garnet surface composition with an acid to form a porous uniform protonated garnet surface composition.

What is claimed: 
     
         1 . A solid garnet composition, comprising:
 a bulk composition comprising a lithium garnet; and   a surface composition comprising a protonated garnet on an exterior surface of the lithium garnet,   wherein the protonated garnet is uniformly disposed over the exterior surface of the lithium garnet.   
     
     
         2 . The composition of  claim 1 , wherein the surface protonated portion of the garnet is compositionally stable in air and insensitive to water and carbon dioxide. 
     
     
         3 . (canceled) 
     
     
         4 . The composition of  claim 1  wherein
 the lithium garnet is Li 7 La 3 Zr 2 O 12  and 
 the protonated garnet is Li (7-x) H x La 3 Zr 2 O 12 , where x is from 0.1 to 7. 
 
     
     
         5 . (canceled) 
     
     
         6 . The composition of  claim 1 , wherein the surface composition comprises a surface free of at least one of LiOH, Li 2 CO 3 , or a combination thereof. 
     
     
         7 - 20 . (canceled)