Hydrothermal synthesis of polymorphic titania and their structural evolution from potassium titanate whisker

The hydrothermal synthesis of polymorphic titania crystals and their structural evolution from potassium titanates, K₂Ti₆O₁₃, K₂Ti₄O₉ and K₂Ti₈O₁₇ whiskers, were studied systematically. Dispersed, regular twinning rutile TiO₂ was firstly generated by hydrothermally treating K₂Ti₆O₁₃ whisker in an acid medium. The crystal phase and morphologies varied with different reaction temperatures and time in diverse mediums were investigated using XRD, SEM and TEM. The results indicate that the weak-binding crystallographic planes are the key factors of the crystal transformation in the hydrothermal system. The transformation from K₂Ti₆O₁₃ to the twinning rutile is achieved via rearranging structural units on the {100} or {201} plane.