BaTi2O5 nanobelts with 60-100 nm in thickness, 200-300 mn in width, and several micrometers in length have been successfully synthesized through a two-step hydrothermal reaction. Sodium titanate nanobelts are synthesized via the reaction of titania nanoparticles and NaOH aqueous solution at 180 degrees C for 24 h. After the reaction, resulting sodium titanate nanobelts are ion-exchanged with barium ions and then treated at 180 degrees C for 60 h under alkaline condition, BaTi2O5 nanobelts are formed. The morphologies and crystal structures of sodium titanate and BaTi2O5 nanobelts are characterized by field-emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM) and X-ray powder diffractometer (XRD), respectively. (c) 2005 Elsevier Ltd. All rights reserved.