Peroxide route for synthesis of magnesium titanate powders of various compositions

Abstract

The magnesium titanates MgTiO 3, Mg 2TiO 4 and MgTi 2O 5 can be sythesized by the wet chemical peroxide route at low temperatures. The first step of the preparation is the precipitation of peroxo-precursors of definite stoichiometry which are transformable into the corresponding titanates by thermal decomposition. The resulting ultrafine, phase-pure magnesium titanate powders have only a low impurity content. They are very sinteractive above 1200°C. The rate of densification during sintering of compacts is improved in the order MgTi 2O 5 < Mg 2TiO 4 < MgTiO 3, including the green densities, the densities at a given time and the theoretical densities of the titanates for the calculations. The Mg 2TiO 4 formation occurs via the inverse spinel phase of Mg 2TiO 4 in a metastable state at low temperatures and MgTiO 3 and MgO as intermediates.