Template induced sol–gel synthesis of highly ordered LaNiO3 nanowires

The highly ordered LaNiO3 nanowires of the rare-earth perovskite-type composite oxide were controlled synthesized within a porous anodic aluminum oxide (AAO) template by means of sol–gel method using nitrate as raw materials and citric acid as chelating agent. The results of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that the obtained LaNiO3 nanowires had a uniform length and diameter, which were determined by the thickness and the pore diameter of the applied AAO template. The results of X-ray diffraction (XRD) and the selected-area electron diffraction (SAED) indicated that the LaNiO3 nanowires were perovskite-type crystalline structures. Furthermore, X-ray photoelectron spectroscopy (XPS) and the energy dispersive X-ray (EDX) spectroscopy demonstrated that the stoichiometric LaNiO3 was formed.