PREPARATION OF ILMENITE TYPE OXIDES VIA ION-EXCHANGE REACTION

Alkaline ions in KSbO3 and NaBiO3.nH2O were ion-exchanged with Li ion. The ilmenite type LiSbO3 was prepared for the first time by ion-exchange of KSbO3 with the ilmenite type structure and the c-axis shrank from 18.213 to 14.57(4) angstrom by replacement of K ion with Li ion. The compound is a metastable phase and transforms to the LiSbO3 type structure at 868-degrees-C. The minimum value of the ratio Na/Li in the ion-exchanged samples of NaBiO3.nH2O was 0.09, although the ion-exchanged compounds were partially decomposed to Bi2O3 during the ion-exchange reaction. The thermal behavior of the ion-exchanged samples is similar to that of NaBiO3.nH2O. By dehydration of the ion-exchanged compound the ilmenite type phase was observed in a multiphase.