The hydrothermal oxidation of Ti metal powder was performed in ca. 0.1-55 mol (kg H2O)-1 caesium hydroxide solutions in the range 150 to 350°C. Lepidocrocite-type caesium titanate (CsxTi2 - x/4□x/4O4) (□ = vacancy) has been successfully obtained as a single phase even at the low temperature of 150°C. Resultant caesium titanate forms plate-like particles with an average size of ca. 0.59 μm in length. At higher caesium hydroxide concentrations and reaction temperatures, amorphous products which transform into CsxTi2 - x/4□ x/4O4 by calcination above 750°C are obtained. A formation diagram of products in the Ti-CsOH-H2O system has been constructed for a CsOH concentration range of 0.1-55 mol (kg H2O)-1 and for the temperature range 150-350°C.
ASJC Scopus subject areas
- Materials Chemistry