delta-Bi2O3 nanowires were successfully fabricated using a thermal enhanced process on electroplated Bi nanowires. Bi was first prepared using template-assisted electroplating. After thermal modification at 350 degrees C for 12 h in air, Bi2O3 nanowires with high-temperature phase (delta-phase) were obtained. A Bi/Bi2O3 core-shell structure was examined by high-resolution transmission electron microscopy (HRTEM) after the Bi nanowires heated at 250 degrees C for 12 h. The oxidation reaction of Bi occurred at temperatures below the melting point of Bi (271.3 degrees C). According to the analysis of HRTEM, the formation of high-temperature delta-phase is caused by the coherent relationship between Bi and Bi2O3 nanowires. (C) 2005 The Electrochemical Society.