Effect of the surface configuration on the oxidation of bismuth nanowire

Incorporating nanoprocessing into the metal oxidation, it was a facile way to synthesize functional oxide with desired nanostructure. In this work, delta-Bi2O3 nanowires were successfully fabricated by the oxidation of electroplated Bi nanowires at 350 degrees C. delta-Bi2O3 is the high-temperature phase of Bi2O3 and only stable at 723-823 degrees C. Partially oxidized nanowires showed core-shell structure composed of metallic Bi and delta-Bi2O3. To investigate the mechanism of oxidation reaction, the Bi/Bi2O3 interface was characterized by high resolution transmission electron microscopy (HRTEM). HRTEM images showed rapid growth of oxide layer on (2 (1) over bar0) plane of rhombohedral Bi metal. The coherency between (101) of metallic Bi and (10 0) of cubic Bi2O3 was observed. A schematic model was also used to describe the. oxidation process. The coherency Bi and Bi2O3 and the stabilization of high-temperature (fluorite structure) Bi2O3 were also discussed based on this model. (c) 2006 Elsevier Ltd. All rights reserved.