Studies on a basic question of zinc titanates

Abstract: Anatase and rutile TiO2 crystalline powders were combined with ZnO powder to synthesize zinc titanates using traditional solid-state reaction method, on the basis of which, the disagreement between experimental results and the well-known hypothesis that the formation of Zn2TiO4 is limited by the presence of anatase whereas ZnTiO3 is formed only in the presence of rutile, a basic but unresolved question, was discussed qualitatively and phenomenologically by means of X-ray diffraction and thermal analysis. On the one hand, a grain size effect of anatase powder on the amount of ZnTiO3 product was found out in ZnO–TiO2 system for the first time, and can well explain the appearance of ZnTiO3 in anatase-derived zinc titanates. On the other hand, a so-called RID process was put forward to interpret the appearance of Zn2TiO4 in rutile-derived zinc titanates calcined at temperatures below the onset decomposition temperature of ZnTiO3, and agreed well with the experimental results. As a result, the reasons for the disagreement mentioned above were naturally exposed, and a key factor in the achievement of pure or, at least a higher mass fraction of ZnTiO3 under solid-state conditions as well. [Copyright &y& Elsevier]