Patent ID: 8900537

Claim:
A method of synthesizing a pyrochlore nanostructure having the general formula A 2 B 2 O 7 , where A and B are rare-earth or transition metal species and O is oxygen, the method comprising: separately mixing together a first acid stabilized aqueous solution including a pyrochlore precursor A and a second acid stabilized aqueous solution including a pyrochlore precursor B with an organic solvent mixture comprising a surfactant and an organic solvent to form a first acid stabilized oil-in-water emulsion of precursor A and a second acid stabilized oil-in-water emulsion of precursor B; mixing together equimolar portions of the first and second acid stabilized oil-in-water emulsions to form a mixed acid stabilized oil-in-water emulsion comprising the pyrochlore precursor A and the pyrochlore precursor B; treating the mixed acid stabilized oil-in-water emulsion with a base to increase the pH from acidic to alkaline to produce a precipitate including the pyrochlore precursors A and B; isolating the precipitate; and calcining the precipitate in the presence of oxygen to form the pyrochlore nanostructure, wherein the method of synthesizing the pyrochlore nanostructure is template-free.