Sol-gel template synthesis and characterization of LaCoO3 nanowires

Densely packed LaCoO3 nanowires of the rare-earth perovskite-type composite oxide were synthesized within a porous anodic aluminum oxide (AAO) template by means of the sol-gel method using nitrate as raw the material and citric acid as the chelating agent. The results of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that the LaCoO3 nanowires possessed a uniform length and diameter, which were controlled by the thickness and the pore diameter of the applied AAO template, respectively. The results of X-ray diffraction (XRD) and the selected area electron diffraction (SAED) indicated that the LaCoO3 nanowires had a rhombohedral perovskite-type crystal structure. Furthermore, X-ray photoelectron spectroscopy (XPS) demonstrated that LaCoO3 nanowires were formed. Finally, the formation mechanism of nanowires was also discussed.