Size-controlled one-dimensional monocrystalline BaTiO₃ nanostructures

One-dimensional BaTiO₃ nanostructures have been synthesized by a simple hydrothermal ion-exchange reaction using alkali-metal titanates as synthetic precursors. The BaTiO₃ nanowires obtained from Na ₂Ti₃O₇ nanowires have diameters of 50-80 nm and lengths of up to 10 μm. In contrast, BaTiO₃ nanowires obtained from K₂Ti₄O₉ nanowhiskers have relatively large sizes of 300-500 nm in diameter and several tens of microns in length. Both types of nanostructures are single-crystalline without any impurity phases. The local electric polarization of individual ferroelectric nanowires has been studied using vertical mode piezoresponse force microscopy.