Hydrothermal Synthesis of Polymorphic Titania and their Structural Evolution from Potassium Titanate Whisker
钛酸钾晶须水热合成多形体TiO2及结构演变

The hydrothermal synthesis of polymorphic titania crystals and their structural evolution from potassium titanates, K2Ti6O13, K2 Ti4O9 and K2Ti8O17 whiskers, were studied systematically. Dispersed, regular twinning rutile TiO2 was firstly generated by hydrothermally treating K2 Ti6O13 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 K2 Ti6O13 to the twinning rutile is achieved via rearranging structural units on the {100} or{ 201} plane.