ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Formation and Surface Structure of Ti-Zn-Double Oxides and of Zn Ferrite

U. Steinike, P. Druska, B. Wallis, D.-Chr. Uecker, and V. SŠepelák

Institute of Applied Chemistry Berlin-AdlershoJ e. V., D-124 84 Berlin

Abstract: In powder mixtures of ZnO and TiO₂ the compounds Zn₂TiO₄, ZnTiO₃, and Zn₂Ti₃O₈ can be formed as a result of solid state reactions. The formation of the double oxides is essentially determined by the microstructure of the powder mixture. Furthermore, the type of the double oxide depends on the TiO₂ modification. There exist structural similarities between Zn₂TiO₄ (spinel) and TiO2 (anatase) as well as between ZnTiO₃  and TiO₂ (rutile). Compound Zn₂Ti₃O₈ is formed only on the basis of the Zn₂TiO₄ phase. The Zn²⁺ ions on the surface of Zn₂Ti₃O₈ occupy only tetrahedral sites and not octahedral ones, like it was derived for the crystal structure of the bulk.The formation of zinc ferrite, ZnFe₂O₄ at room temperature is possible by means of mechanical activation in a high-energy ball-milling process of a ZnO-Fe₂O₃ mixture (mechanosynthesis). The surface structure of mechanosynthesized zinc ferrite corresponds to the inverse spinel structure type. The structure of inverse spinel type is also created by means of mechanical activation of zinc ferrite of the normal spinel type.

Full paper in Portable Document Format: 523a147.pdf

Chemical Papers 52 (3) 147–151 (1998)