Characterization of Ni nanowires after annealing

The effect of Ni nanowires, fabricated by electrodeposition in self-ordered AAO templates, was studied. NiO and Ni2O3 nanofibers were fabricated by simple heat-treatment in air and in an atmosphere of pure O-2. Ni nanowires after vacuum annealing exhibit pronounced preferential orientation of Ni (111) at 600 degrees C. Grain growth resulted in size effects and induced the transformation of NiO to Ni2O3 during annealing in air. Ni was oxidized to Ni2O3 (similar to 500 degrees C) in an atmosphere of pure O-2. The stable Ni-oxides Ni2O3 are formed during annealing at a higher temperature (similar to 900 degrees C) in air and in an atmosphere of pure O-2. (c) 2006 Elsevier B.V. All rights reserved.