Ion-exchanging Preparation and Characterization of Potassium Titanate Nanofiber

Potassium titanate nanofibers (K1.34H0.66Ti2O4(OH)2) were prepared by using ion-exchange reaction between KOH solution and titanic acid nanotube (H2Ti204(OH)2). TEM and XRD results show that the nanotubes change into nanofibers and the crystalline structure alters. K/Ti atomic ratio, chemical state of K and Ti elements for the product were determined by means of atomic absorption spectrophotometry, colorimetric method, and X-ray photoelectron spectroscopy. The results indicate that the empirical formula of the product is K1.34Ho.66Ti2O4(OH)2. Compared with H2Ti2O4(OH)2 nanotubes, the thermal-stability of potassium titanate nanofibers is higher. At T 700℃, the crystalline structure of this material changes into monoclinic phase K2Ti4Og. High temperature treatment results in nanofibers' sizes increasing, but the aspect ratio is still high. The BET surface area of the material is 104m2·g-1.